diff --git a/examples/CameraResectioning.cpp b/examples/CameraResectioning.cpp
index 9ba415b7d..891269f16 100644
--- a/examples/CameraResectioning.cpp
+++ b/examples/CameraResectioning.cpp
@@ -16,7 +16,7 @@
  * @date    Aug 23, 2011
  */
 
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/nonlinear/LevenbergMarquardtOptimizer.h>
 #include <gtsam/geometry/SimpleCamera.h>
 #include <boost/make_shared.hpp>
diff --git a/examples/PlanarSLAMExample.cpp b/examples/PlanarSLAMExample.cpp
index e671c0fd9..5a8624db0 100644
--- a/examples/PlanarSLAMExample.cpp
+++ b/examples/PlanarSLAMExample.cpp
@@ -33,7 +33,7 @@
 // Each variable in the system (poses and landmarks) must be identified with a unique key.
 // We can either use simple integer keys (1, 2, 3, ...) or symbols (X1, X2, L1).
 // Here we will use Symbols
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 // In GTSAM, measurement functions are represented as 'factors'. Several common factors
 // have been provided with the library for solving robotics/SLAM/Bundle Adjustment problems.
diff --git a/examples/RangeISAMExample_plaza2.cpp b/examples/RangeISAMExample_plaza2.cpp
index fc2edb7e1..29b02a271 100644
--- a/examples/RangeISAMExample_plaza2.cpp
+++ b/examples/RangeISAMExample_plaza2.cpp
@@ -22,7 +22,7 @@
 // Each variable in the system (poses and landmarks) must be identified with a unique key.
 // We can either use simple integer keys (1, 2, 3, ...) or symbols (X1, X2, L1).
 // Here we will use Symbols
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 // We want to use iSAM2 to solve the range-SLAM problem incrementally
 #include <gtsam/nonlinear/ISAM2.h>
diff --git a/examples/SimpleRotation.cpp b/examples/SimpleRotation.cpp
index 830b202cb..1f40d8c60 100644
--- a/examples/SimpleRotation.cpp
+++ b/examples/SimpleRotation.cpp
@@ -28,7 +28,7 @@
 // Each variable in the system (poses) must be identified with a unique key.
 // We can either use simple integer keys (1, 2, 3, ...) or symbols (X1, X2, L1).
 // Here we will use symbols
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 // In GTSAM, measurement functions are represented as 'factors'. Several common factors
 // have been provided with the library for solving robotics/SLAM/Bundle Adjustment problems.
diff --git a/examples/SolverComparer.cpp b/examples/SolverComparer.cpp
index 3a174ca51..6bdb8cf26 100644
--- a/examples/SolverComparer.cpp
+++ b/examples/SolverComparer.cpp
@@ -20,7 +20,7 @@
 #include <gtsam/slam/PriorFactor.h>
 #include <gtsam/slam/BetweenFactor.h>
 #include <gtsam/slam/BearingRangeFactor.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/nonlinear/ISAM2.h>
 #include <gtsam/nonlinear/GaussNewtonOptimizer.h>
 #include <gtsam/nonlinear/Marginals.h>
diff --git a/examples/VisualISAM2Example.cpp b/examples/VisualISAM2Example.cpp
index 0f403ec8a..50574a0a8 100644
--- a/examples/VisualISAM2Example.cpp
+++ b/examples/VisualISAM2Example.cpp
@@ -34,7 +34,7 @@
 // Each variable in the system (poses and landmarks) must be identified with a unique key.
 // We can either use simple integer keys (1, 2, 3, ...) or symbols (X1, X2, L1).
 // Here we will use Symbols
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 // We want to use iSAM2 to solve the structure-from-motion problem incrementally, so
 // include iSAM2 here
diff --git a/examples/VisualISAMExample.cpp b/examples/VisualISAMExample.cpp
index e3f8bbacd..43d0ae273 100644
--- a/examples/VisualISAMExample.cpp
+++ b/examples/VisualISAMExample.cpp
@@ -34,7 +34,7 @@
 // Each variable in the system (poses and landmarks) must be identified with a unique key.
 // We can either use simple integer keys (1, 2, 3, ...) or symbols (X1, X2, L1).
 // Here we will use Symbols
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 // In GTSAM, measurement functions are represented as 'factors'. Several common factors
 // have been provided with the library for solving robotics/SLAM/Bundle Adjustment problems.
diff --git a/examples/VisualSLAMExample.cpp b/examples/VisualSLAMExample.cpp
index dd2d27d0c..4a07e201b 100644
--- a/examples/VisualSLAMExample.cpp
+++ b/examples/VisualSLAMExample.cpp
@@ -33,7 +33,7 @@
 // Each variable in the system (poses and landmarks) must be identified with a unique key.
 // We can either use simple integer keys (1, 2, 3, ...) or symbols (X1, X2, L1).
 // Here we will use Symbols
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 // In GTSAM, measurement functions are represented as 'factors'. Several common factors
 // have been provided with the library for solving robotics/SLAM/Bundle Adjustment problems.
diff --git a/examples/easyPoint2KalmanFilter.cpp b/examples/easyPoint2KalmanFilter.cpp
index 6d75e9149..2660f846f 100644
--- a/examples/easyPoint2KalmanFilter.cpp
+++ b/examples/easyPoint2KalmanFilter.cpp
@@ -22,7 +22,7 @@
  */
 
 #include <gtsam/nonlinear/ExtendedKalmanFilter.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/slam/PriorFactor.h>
 #include <gtsam/slam/BetweenFactor.h>
 #include <gtsam/geometry/Point2.h>
diff --git a/examples/elaboratePoint2KalmanFilter.cpp b/examples/elaboratePoint2KalmanFilter.cpp
index 218b031fd..049d1a015 100644
--- a/examples/elaboratePoint2KalmanFilter.cpp
+++ b/examples/elaboratePoint2KalmanFilter.cpp
@@ -23,7 +23,7 @@
 #include <gtsam/slam/PriorFactor.h>
 #include <gtsam/slam/BetweenFactor.h>
 //#include <gtsam/nonlinear/Ordering.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/linear/GaussianBayesNet.h>
 #include <gtsam/linear/GaussianFactorGraph.h>
 #include <gtsam/linear/NoiseModel.h>
diff --git a/gtsam.h b/gtsam.h
index 5cee11629..5aa6d4f22 100644
--- a/gtsam.h
+++ b/gtsam.h
@@ -1456,7 +1456,7 @@ class KalmanFilter {
 // nonlinear
 //*************************************************************************
 
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 size_t symbol(char chr, size_t index);
 char symbolChr(size_t key);
 size_t symbolIndex(size_t key);
@@ -1465,7 +1465,7 @@ size_t symbolIndex(size_t key);
 void printKeySet(const gtsam::KeySet& keys);
 void printKeySet(const gtsam::KeySet& keys, string s);
 
-#include <gtsam/nonlinear/LabeledSymbol.h>
+#include <gtsam/inference/LabeledSymbol.h>
 class LabeledSymbol {
   LabeledSymbol(size_t full_key);
   LabeledSymbol(const gtsam::LabeledSymbol& key);
diff --git a/gtsam/base/types.cpp b/gtsam/base/types.cpp
index 8b783d512..00eb50702 100644
--- a/gtsam/base/types.cpp
+++ b/gtsam/base/types.cpp
@@ -20,7 +20,7 @@
 #include <boost/lexical_cast.hpp>
 
 #include <gtsam/base/types.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 namespace gtsam {
 
diff --git a/gtsam/inference/Key.cpp b/gtsam/inference/Key.cpp
index b986154df..3b73725bc 100644
--- a/gtsam/inference/Key.cpp
+++ b/gtsam/inference/Key.cpp
@@ -23,7 +23,7 @@
 #include <boost/foreach.hpp>
 
 #include <gtsam/inference/Key.h>
-#include <gtsam/nonlinear/LabeledSymbol.h>
+#include <gtsam/inference/LabeledSymbol.h>
 
 namespace gtsam {
 
diff --git a/gtsam/nonlinear/LabeledSymbol.cpp b/gtsam/inference/LabeledSymbol.cpp
similarity index 99%
rename from gtsam/nonlinear/LabeledSymbol.cpp
rename to gtsam/inference/LabeledSymbol.cpp
index 97272e873..7e573c13f 100644
--- a/gtsam/nonlinear/LabeledSymbol.cpp
+++ b/gtsam/inference/LabeledSymbol.cpp
@@ -26,7 +26,7 @@
 
 #include <boost/lexical_cast.hpp>
 
-#include <gtsam/nonlinear/LabeledSymbol.h>
+#include <gtsam/inference/LabeledSymbol.h>
 
 namespace gtsam {
 
diff --git a/gtsam/nonlinear/LabeledSymbol.h b/gtsam/inference/LabeledSymbol.h
similarity index 99%
rename from gtsam/nonlinear/LabeledSymbol.h
rename to gtsam/inference/LabeledSymbol.h
index eaa7f373f..4b125988c 100644
--- a/gtsam/nonlinear/LabeledSymbol.h
+++ b/gtsam/inference/LabeledSymbol.h
@@ -19,7 +19,7 @@
 
 #pragma once
 
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 namespace gtsam {
 
diff --git a/gtsam/nonlinear/Symbol.cpp b/gtsam/inference/Symbol.cpp
similarity index 98%
rename from gtsam/nonlinear/Symbol.cpp
rename to gtsam/inference/Symbol.cpp
index d2d756626..37a6d0897 100644
--- a/gtsam/nonlinear/Symbol.cpp
+++ b/gtsam/inference/Symbol.cpp
@@ -16,7 +16,7 @@
  * @author: Richard Roberts
  */
 
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 #include <boost/mpl/char.hpp>
 #include <boost/format.hpp>
diff --git a/gtsam/nonlinear/Symbol.h b/gtsam/inference/Symbol.h
similarity index 100%
rename from gtsam/nonlinear/Symbol.h
rename to gtsam/inference/Symbol.h
diff --git a/gtsam/nonlinear/tests/testKey.cpp b/gtsam/inference/tests/testKey.cpp
similarity index 98%
rename from gtsam/nonlinear/tests/testKey.cpp
rename to gtsam/inference/tests/testKey.cpp
index ee9734af5..8eb840cbc 100644
--- a/gtsam/nonlinear/tests/testKey.cpp
+++ b/gtsam/inference/tests/testKey.cpp
@@ -20,7 +20,7 @@ using namespace boost::assign;
 #include <CppUnitLite/TestHarness.h>
 #include <gtsam/base/Testable.h>
 #include <gtsam/base/TestableAssertions.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 using namespace std;
 using namespace gtsam;
diff --git a/gtsam/nonlinear/tests/testLabeledSymbol.cpp b/gtsam/inference/tests/testLabeledSymbol.cpp
similarity index 98%
rename from gtsam/nonlinear/tests/testLabeledSymbol.cpp
rename to gtsam/inference/tests/testLabeledSymbol.cpp
index 107c4502e..f8b785eb7 100644
--- a/gtsam/nonlinear/tests/testLabeledSymbol.cpp
+++ b/gtsam/inference/tests/testLabeledSymbol.cpp
@@ -21,7 +21,7 @@ using namespace boost::assign;
 #include <gtsam/base/Testable.h>
 #include <gtsam/base/TestableAssertions.h>
 
-#include <gtsam/nonlinear/LabeledSymbol.h>
+#include <gtsam/inference/LabeledSymbol.h>
   
 using namespace std;
 using namespace gtsam;
diff --git a/gtsam/inference/tests/testOrdering.cpp b/gtsam/inference/tests/testOrdering.cpp
index 2443dba2a..3bf6f7ca0 100644
--- a/gtsam/inference/tests/testOrdering.cpp
+++ b/gtsam/inference/tests/testOrdering.cpp
@@ -14,7 +14,7 @@
  * @author Alex Cunningham
  */
 
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/symbolic/SymbolicFactorGraph.h>
 #include <gtsam/inference/Ordering.h>
 #include <gtsam/base/TestableAssertions.h>
diff --git a/gtsam/navigation/tests/testCombinedImuFactor.cpp b/gtsam/navigation/tests/testCombinedImuFactor.cpp
index 66d62ef22..fba083892 100644
--- a/gtsam/navigation/tests/testCombinedImuFactor.cpp
+++ b/gtsam/navigation/tests/testCombinedImuFactor.cpp
@@ -16,7 +16,7 @@
  */
 
 #include <gtsam/nonlinear/Values.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/navigation/ImuFactor.h>
 #include <gtsam/navigation/CombinedImuFactor.h>
 #include <gtsam/navigation/ImuBias.h>
diff --git a/gtsam/navigation/tests/testImuFactor.cpp b/gtsam/navigation/tests/testImuFactor.cpp
index e312df60c..2db7c7c68 100644
--- a/gtsam/navigation/tests/testImuFactor.cpp
+++ b/gtsam/navigation/tests/testImuFactor.cpp
@@ -17,7 +17,7 @@
 
 #include <gtsam/navigation/ImuFactor.h>
 #include <gtsam/nonlinear/Values.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/navigation/ImuBias.h>
 #include <gtsam/geometry/Pose3.h>
 #include <gtsam/base/LieVector.h>
diff --git a/gtsam/nonlinear/ISAM2-impl.cpp b/gtsam/nonlinear/ISAM2-impl.cpp
index 38c087741..23be20faf 100644
--- a/gtsam/nonlinear/ISAM2-impl.cpp
+++ b/gtsam/nonlinear/ISAM2-impl.cpp
@@ -17,7 +17,7 @@
  */
 
 #include <gtsam/nonlinear/ISAM2-impl.h>
-#include <gtsam/nonlinear/Symbol.h> // for selective linearization thresholds
+#include <gtsam/inference/Symbol.h> // for selective linearization thresholds
 #include <gtsam/base/debug.h>
 #include <functional>
 #include <boost/range/adaptors.hpp>
diff --git a/gtsam/nonlinear/tests/testSerializationNonlinear.cpp b/gtsam/nonlinear/tests/testSerializationNonlinear.cpp
index 95bb4d93e..ee2f0d793 100644
--- a/gtsam/nonlinear/tests/testSerializationNonlinear.cpp
+++ b/gtsam/nonlinear/tests/testSerializationNonlinear.cpp
@@ -17,7 +17,7 @@
  */
 
 #include <gtsam/nonlinear/Values.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/geometry/PinholeCamera.h>
 #include <gtsam/geometry/Cal3_S2.h>
 #include <gtsam/geometry/Cal3DS2.h>
diff --git a/gtsam/nonlinear/tests/testValues.cpp b/gtsam/nonlinear/tests/testValues.cpp
index cb4973ef5..d03f78424 100644
--- a/gtsam/nonlinear/tests/testValues.cpp
+++ b/gtsam/nonlinear/tests/testValues.cpp
@@ -15,7 +15,7 @@
  */
 
 #include <gtsam/nonlinear/Values.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/linear/VectorValues.h>
 #include <gtsam/geometry/Pose2.h>
 #include <gtsam/geometry/Pose3.h>
diff --git a/gtsam/slam/dataset.cpp b/gtsam/slam/dataset.cpp
index 36d26f308..465b378ff 100644
--- a/gtsam/slam/dataset.cpp
+++ b/gtsam/slam/dataset.cpp
@@ -24,7 +24,7 @@
 
 #include <gtsam/geometry/Pose2.h>
 #include <gtsam/linear/Sampler.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/slam/dataset.h>
 #include <gtsam/slam/BetweenFactor.h>
 #include <gtsam/slam/BearingRangeFactor.h>
diff --git a/gtsam/slam/tests/testBetweenFactor.cpp b/gtsam/slam/tests/testBetweenFactor.cpp
index c9cd6c07a..44d401afd 100644
--- a/gtsam/slam/tests/testBetweenFactor.cpp
+++ b/gtsam/slam/tests/testBetweenFactor.cpp
@@ -7,7 +7,7 @@
 
 #include <gtsam/base/numericalDerivative.h>
 #include <gtsam/geometry/Rot3.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/slam/BetweenFactor.h>
 #include <CppUnitLite/TestHarness.h>
 
diff --git a/gtsam/slam/tests/testGeneralSFMFactor.cpp b/gtsam/slam/tests/testGeneralSFMFactor.cpp
index e6d134ee6..e05140875 100644
--- a/gtsam/slam/tests/testGeneralSFMFactor.cpp
+++ b/gtsam/slam/tests/testGeneralSFMFactor.cpp
@@ -20,7 +20,7 @@
 #include <gtsam/slam/RangeFactor.h>
 #include <gtsam/slam/PriorFactor.h>
 #include <gtsam/nonlinear/NonlinearEquality.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/LevenbergMarquardtOptimizer.h>
 #include <gtsam/linear/VectorValues.h>
diff --git a/gtsam/slam/tests/testGeneralSFMFactor_Cal3Bundler.cpp b/gtsam/slam/tests/testGeneralSFMFactor_Cal3Bundler.cpp
index 98ae401fc..0c89fba18 100644
--- a/gtsam/slam/tests/testGeneralSFMFactor_Cal3Bundler.cpp
+++ b/gtsam/slam/tests/testGeneralSFMFactor_Cal3Bundler.cpp
@@ -20,7 +20,7 @@
 #include <gtsam/slam/RangeFactor.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/NonlinearEquality.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/nonlinear/LevenbergMarquardtOptimizer.h>
 #include <gtsam/linear/VectorValues.h>
 #include <gtsam/geometry/Point3.h>
diff --git a/gtsam/slam/tests/testProjectionFactor.cpp b/gtsam/slam/tests/testProjectionFactor.cpp
index fc1d9a51b..9c7236054 100644
--- a/gtsam/slam/tests/testProjectionFactor.cpp
+++ b/gtsam/slam/tests/testProjectionFactor.cpp
@@ -17,7 +17,7 @@
  */
 
 #include <gtsam/slam/ProjectionFactor.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/geometry/Cal3DS2.h>
 #include <gtsam/geometry/Cal3_S2.h>
 #include <gtsam/geometry/Pose3.h>
diff --git a/gtsam/slam/tests/testReferenceFrameFactor.cpp b/gtsam/slam/tests/testReferenceFrameFactor.cpp
index 5735ac21c..078bf85cd 100644
--- a/gtsam/slam/tests/testReferenceFrameFactor.cpp
+++ b/gtsam/slam/tests/testReferenceFrameFactor.cpp
@@ -23,7 +23,7 @@
 #include <gtsam/base/Testable.h>
 #include <gtsam/base/numericalDerivative.h>
 #include <gtsam/geometry/Pose2.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/NonlinearEquality.h>
 #include <gtsam/nonlinear/LevenbergMarquardtOptimizer.h>
diff --git a/gtsam/slam/tests/testStereoFactor.cpp b/gtsam/slam/tests/testStereoFactor.cpp
index 3c28f6da9..3a2fbd4f4 100644
--- a/gtsam/slam/tests/testStereoFactor.cpp
+++ b/gtsam/slam/tests/testStereoFactor.cpp
@@ -20,7 +20,7 @@
 #include <gtsam/nonlinear/GaussNewtonOptimizer.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/Values.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/geometry/StereoCamera.h>
 #include <gtsam/geometry/Cal3_S2Stereo.h>
 #include <gtsam/geometry/Pose3.h>
diff --git a/gtsam/symbolic/tests/symbolicExampleGraphs.h b/gtsam/symbolic/tests/symbolicExampleGraphs.h
index c49633b53..8b7c32bd9 100644
--- a/gtsam/symbolic/tests/symbolicExampleGraphs.h
+++ b/gtsam/symbolic/tests/symbolicExampleGraphs.h
@@ -25,7 +25,7 @@
 #include <gtsam/symbolic/SymbolicConditional.h>
 #include <gtsam/symbolic/SymbolicBayesTree.h>
 #include <gtsam/inference/Ordering.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <boost/assign/list_of.hpp>
 
 namespace gtsam {
diff --git a/gtsam/symbolic/tests/testSymbolicBayesTree.cpp b/gtsam/symbolic/tests/testSymbolicBayesTree.cpp
index 521733795..52e13e3d2 100644
--- a/gtsam/symbolic/tests/testSymbolicBayesTree.cpp
+++ b/gtsam/symbolic/tests/testSymbolicBayesTree.cpp
@@ -19,7 +19,7 @@
 
 #include <gtsam/symbolic/SymbolicBayesTree.h>
 #include <gtsam/symbolic/SymbolicBayesNet.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/symbolic/tests/symbolicExampleGraphs.h>
 
 #include <boost/assign/list_of.hpp>
diff --git a/gtsam/symbolic/tests/testSymbolicEliminationTree.cpp b/gtsam/symbolic/tests/testSymbolicEliminationTree.cpp
index c6d4c8937..38ec08411 100644
--- a/gtsam/symbolic/tests/testSymbolicEliminationTree.cpp
+++ b/gtsam/symbolic/tests/testSymbolicEliminationTree.cpp
@@ -23,7 +23,7 @@
 
 #include <gtsam/base/TestableAssertions.h>
 #include <gtsam/symbolic/SymbolicEliminationTree.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 #include "symbolicExampleGraphs.h"
 
diff --git a/gtsam_unstable/dynamics/tests/testPendulumFactors.cpp b/gtsam_unstable/dynamics/tests/testPendulumFactors.cpp
index e841fba3a..ce176787c 100644
--- a/gtsam_unstable/dynamics/tests/testPendulumFactors.cpp
+++ b/gtsam_unstable/dynamics/tests/testPendulumFactors.cpp
@@ -4,7 +4,7 @@
  */
 
 #include <CppUnitLite/TestHarness.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam_unstable/dynamics/Pendulum.h>
 
 /* ************************************************************************* */
diff --git a/gtsam_unstable/dynamics/tests/testSimpleHelicopter.cpp b/gtsam_unstable/dynamics/tests/testSimpleHelicopter.cpp
index 4c052f704..09f67f527 100644
--- a/gtsam_unstable/dynamics/tests/testSimpleHelicopter.cpp
+++ b/gtsam_unstable/dynamics/tests/testSimpleHelicopter.cpp
@@ -5,7 +5,7 @@
 
 #include <CppUnitLite/TestHarness.h>
 #include <gtsam/base/numericalDerivative.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam_unstable/dynamics/SimpleHelicopter.h>
 
 /* ************************************************************************* */
diff --git a/gtsam_unstable/dynamics/tests/testVelocityConstraint3.cpp b/gtsam_unstable/dynamics/tests/testVelocityConstraint3.cpp
index 55880ef97..db4b7c586 100644
--- a/gtsam_unstable/dynamics/tests/testVelocityConstraint3.cpp
+++ b/gtsam_unstable/dynamics/tests/testVelocityConstraint3.cpp
@@ -5,7 +5,7 @@
 
 #include <CppUnitLite/TestHarness.h>
 
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam_unstable/dynamics/VelocityConstraint3.h>
 
 /* ************************************************************************* */
diff --git a/gtsam_unstable/examples/SmartProjectionFactorExample_kitti.cpp b/gtsam_unstable/examples/SmartProjectionFactorExample_kitti.cpp
index afcd85124..80b2cc90f 100644
--- a/gtsam_unstable/examples/SmartProjectionFactorExample_kitti.cpp
+++ b/gtsam_unstable/examples/SmartProjectionFactorExample_kitti.cpp
@@ -22,7 +22,7 @@
 // Each variable in the system (poses and landmarks) must be identified with a unique key.
 // We can either use simple integer keys (1, 2, 3, ...) or symbols (X1, X2, L1).
 // Here we will use Symbols
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 // We want to use iSAM2 to solve the range-SLAM problem incrementally
 #include <gtsam/nonlinear/ISAM2.h>
diff --git a/gtsam_unstable/examples/SmartRangeExample_plaza1.cpp b/gtsam_unstable/examples/SmartRangeExample_plaza1.cpp
index 7a7a921f7..6cc8a7b78 100644
--- a/gtsam_unstable/examples/SmartRangeExample_plaza1.cpp
+++ b/gtsam_unstable/examples/SmartRangeExample_plaza1.cpp
@@ -22,7 +22,7 @@
 // Each variable in the system (poses and landmarks) must be identified with a unique key.
 // We can either use simple integer keys (1, 2, 3, ...) or symbols (X1, X2, L1).
 // Here we will use Symbols
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 // We want to use iSAM2 to solve the range-SLAM problem incrementally
 #include <gtsam/nonlinear/ISAM2.h>
diff --git a/gtsam_unstable/examples/SmartRangeExample_plaza2.cpp b/gtsam_unstable/examples/SmartRangeExample_plaza2.cpp
index 5291d2f88..b689179a2 100644
--- a/gtsam_unstable/examples/SmartRangeExample_plaza2.cpp
+++ b/gtsam_unstable/examples/SmartRangeExample_plaza2.cpp
@@ -22,7 +22,7 @@
 // Each variable in the system (poses and landmarks) must be identified with a unique key.
 // We can either use simple integer keys (1, 2, 3, ...) or symbols (X1, X2, L1).
 // Here we will use Symbols
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 // We want to use iSAM2 to solve the range-SLAM problem incrementally
 #include <gtsam/nonlinear/ISAM2.h>
diff --git a/gtsam_unstable/nonlinear/tests/testConcurrentBatchFilter.cpp b/gtsam_unstable/nonlinear/tests/testConcurrentBatchFilter.cpp
index 95b637d06..c60c5bb37 100644
--- a/gtsam_unstable/nonlinear/tests/testConcurrentBatchFilter.cpp
+++ b/gtsam_unstable/nonlinear/tests/testConcurrentBatchFilter.cpp
@@ -24,7 +24,7 @@
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/LinearContainerFactor.h>
 #include <gtsam/nonlinear/Values.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/inference/Ordering.h>
 #include <gtsam/inference/Key.h>
 #include <gtsam/inference/JunctionTree.h>
diff --git a/gtsam_unstable/nonlinear/tests/testConcurrentBatchSmoother.cpp b/gtsam_unstable/nonlinear/tests/testConcurrentBatchSmoother.cpp
index f4b5c3dea..c6d7a0a0e 100644
--- a/gtsam_unstable/nonlinear/tests/testConcurrentBatchSmoother.cpp
+++ b/gtsam_unstable/nonlinear/tests/testConcurrentBatchSmoother.cpp
@@ -24,7 +24,7 @@
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/LinearContainerFactor.h>
 #include <gtsam/nonlinear/Values.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/inference/Ordering.h>
 #include <gtsam/inference/Key.h>
 #include <gtsam/inference/JunctionTree.h>
diff --git a/gtsam_unstable/nonlinear/tests/testConcurrentIncrementalFilter.cpp b/gtsam_unstable/nonlinear/tests/testConcurrentIncrementalFilter.cpp
index 6fda6dcad..6c6edd4e6 100644
--- a/gtsam_unstable/nonlinear/tests/testConcurrentIncrementalFilter.cpp
+++ b/gtsam_unstable/nonlinear/tests/testConcurrentIncrementalFilter.cpp
@@ -24,7 +24,7 @@
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/LinearContainerFactor.h>
 #include <gtsam/nonlinear/Values.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/inference/Key.h>
 #include <gtsam/inference/JunctionTree.h>
 #include <gtsam/geometry/Pose3.h>
diff --git a/gtsam_unstable/nonlinear/tests/testConcurrentIncrementalSmootherDL.cpp b/gtsam_unstable/nonlinear/tests/testConcurrentIncrementalSmootherDL.cpp
index 03f322ec6..969af2560 100644
--- a/gtsam_unstable/nonlinear/tests/testConcurrentIncrementalSmootherDL.cpp
+++ b/gtsam_unstable/nonlinear/tests/testConcurrentIncrementalSmootherDL.cpp
@@ -24,7 +24,7 @@
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/LinearContainerFactor.h>
 #include <gtsam/nonlinear/Values.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/inference/Key.h>
 #include <gtsam/inference/Ordering.h>
 #include <gtsam/inference/JunctionTree.h>
diff --git a/gtsam_unstable/nonlinear/tests/testConcurrentIncrementalSmootherGN.cpp b/gtsam_unstable/nonlinear/tests/testConcurrentIncrementalSmootherGN.cpp
index 8de7dc56d..56935b876 100644
--- a/gtsam_unstable/nonlinear/tests/testConcurrentIncrementalSmootherGN.cpp
+++ b/gtsam_unstable/nonlinear/tests/testConcurrentIncrementalSmootherGN.cpp
@@ -24,7 +24,7 @@
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/LinearContainerFactor.h>
 #include <gtsam/nonlinear/Values.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/inference/Key.h>
 #include <gtsam/inference/JunctionTree.h>
 #include <gtsam/geometry/Pose3.h>
diff --git a/gtsam_unstable/nonlinear/tests/testIncrementalFixedLagSmoother.cpp b/gtsam_unstable/nonlinear/tests/testIncrementalFixedLagSmoother.cpp
index e67f1a346..56675187d 100644
--- a/gtsam_unstable/nonlinear/tests/testIncrementalFixedLagSmoother.cpp
+++ b/gtsam_unstable/nonlinear/tests/testIncrementalFixedLagSmoother.cpp
@@ -29,7 +29,7 @@
 #include <gtsam/slam/BetweenFactor.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/Values.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 using namespace std;
 using namespace gtsam;
diff --git a/gtsam_unstable/slam/serialization.cpp b/gtsam_unstable/slam/serialization.cpp
index 304b10b6d..2f54528b8 100644
--- a/gtsam_unstable/slam/serialization.cpp
+++ b/gtsam_unstable/slam/serialization.cpp
@@ -19,7 +19,7 @@
 #include <gtsam/slam/RangeFactor.h>
 #include <gtsam/slam/StereoFactor.h>
 #include <gtsam/nonlinear/NonlinearEquality.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/linear/GaussianISAM.h>
 #include <gtsam/linear/GaussianMultifrontalSolver.h>
 #include <gtsam/base/LieVector.h>
diff --git a/gtsam_unstable/slam/tests/testInvDepthFactor3.cpp b/gtsam_unstable/slam/tests/testInvDepthFactor3.cpp
index 21f2bc4dc..65cc1adbc 100644
--- a/gtsam_unstable/slam/tests/testInvDepthFactor3.cpp
+++ b/gtsam_unstable/slam/tests/testInvDepthFactor3.cpp
@@ -11,7 +11,7 @@
 #include <gtsam/nonlinear/NonlinearEquality.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/LevenbergMarquardtOptimizer.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 #include <gtsam_unstable/slam/InvDepthFactor3.h>
 
diff --git a/gtsam_unstable/slam/tests/testInvDepthFactorVariant1.cpp b/gtsam_unstable/slam/tests/testInvDepthFactorVariant1.cpp
index b8f24dda8..bdb36bc0a 100644
--- a/gtsam_unstable/slam/tests/testInvDepthFactorVariant1.cpp
+++ b/gtsam_unstable/slam/tests/testInvDepthFactorVariant1.cpp
@@ -10,7 +10,7 @@
 #include <gtsam/nonlinear/NonlinearEquality.h>
 #include <gtsam/nonlinear/LevenbergMarquardtOptimizer.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/geometry/PinholeCamera.h>
 #include <gtsam/geometry/Cal3_S2.h>
 #include <gtsam/geometry/Pose3.h>
diff --git a/gtsam_unstable/slam/tests/testInvDepthFactorVariant2.cpp b/gtsam_unstable/slam/tests/testInvDepthFactorVariant2.cpp
index 4706a9338..b784d87f4 100644
--- a/gtsam_unstable/slam/tests/testInvDepthFactorVariant2.cpp
+++ b/gtsam_unstable/slam/tests/testInvDepthFactorVariant2.cpp
@@ -10,7 +10,7 @@
 #include <gtsam/nonlinear/NonlinearEquality.h>
 #include <gtsam/nonlinear/LevenbergMarquardtOptimizer.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/geometry/PinholeCamera.h>
 #include <gtsam/geometry/Cal3_S2.h>
 #include <gtsam/geometry/Pose3.h>
diff --git a/gtsam_unstable/slam/tests/testInvDepthFactorVariant3.cpp b/gtsam_unstable/slam/tests/testInvDepthFactorVariant3.cpp
index c15998507..5f5e8c35f 100644
--- a/gtsam_unstable/slam/tests/testInvDepthFactorVariant3.cpp
+++ b/gtsam_unstable/slam/tests/testInvDepthFactorVariant3.cpp
@@ -10,7 +10,7 @@
 #include <gtsam/nonlinear/NonlinearEquality.h>
 #include <gtsam/nonlinear/LevenbergMarquardtOptimizer.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/geometry/PinholeCamera.h>
 #include <gtsam/geometry/Cal3_S2.h>
 #include <gtsam/geometry/Pose3.h>
diff --git a/gtsam_unstable/slam/tests/testMultiProjectionFactor.cpp b/gtsam_unstable/slam/tests/testMultiProjectionFactor.cpp
index a0f692e9e..0d1976a24 100644
--- a/gtsam_unstable/slam/tests/testMultiProjectionFactor.cpp
+++ b/gtsam_unstable/slam/tests/testMultiProjectionFactor.cpp
@@ -26,7 +26,7 @@
 #include <gtsam/nonlinear/LinearContainerFactor.h>
 #include <gtsam/inference/Ordering.h>
 #include <gtsam/nonlinear/Values.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/inference/Key.h>
 #include <gtsam/inference/JunctionTree.h>
 #include <gtsam/geometry/Pose3.h>
diff --git a/gtsam_unstable/slam/tests/testPoseBetweenFactor.cpp b/gtsam_unstable/slam/tests/testPoseBetweenFactor.cpp
index 3063571cc..2fc471eab 100644
--- a/gtsam_unstable/slam/tests/testPoseBetweenFactor.cpp
+++ b/gtsam_unstable/slam/tests/testPoseBetweenFactor.cpp
@@ -17,7 +17,7 @@
  */
 
 #include <gtsam_unstable/slam/PoseBetweenFactor.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/geometry/Pose3.h>
 #include <gtsam/base/numericalDerivative.h>
 #include <gtsam/base/TestableAssertions.h>
diff --git a/gtsam_unstable/slam/tests/testPosePriorFactor.cpp b/gtsam_unstable/slam/tests/testPosePriorFactor.cpp
index c9825d582..27bcd55ce 100644
--- a/gtsam_unstable/slam/tests/testPosePriorFactor.cpp
+++ b/gtsam_unstable/slam/tests/testPosePriorFactor.cpp
@@ -17,7 +17,7 @@
  */
 
 #include <gtsam_unstable/slam/PosePriorFactor.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/geometry/Pose3.h>
 #include <gtsam/base/numericalDerivative.h>
 #include <gtsam/base/TestableAssertions.h>
diff --git a/gtsam_unstable/slam/tests/testSmartProjectionFactor.cpp b/gtsam_unstable/slam/tests/testSmartProjectionFactor.cpp
index 721c3e1a3..3f2912c2e 100644
--- a/gtsam_unstable/slam/tests/testSmartProjectionFactor.cpp
+++ b/gtsam_unstable/slam/tests/testSmartProjectionFactor.cpp
@@ -31,7 +31,7 @@
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/LinearContainerFactor.h>
 #include <gtsam/nonlinear/Values.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/inference/JunctionTree.h>
 #include <gtsam_unstable/geometry/triangulation.h>
 #include <gtsam/geometry/Pose3.h>
diff --git a/tests/smallExample.h b/tests/smallExample.h
index 26ed41a27..518ca3e0c 100644
--- a/tests/smallExample.h
+++ b/tests/smallExample.h
@@ -22,7 +22,7 @@
 #pragma once
 
 #include <tests/simulated2D.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/linear/GaussianBayesNet.h>
 #include <gtsam/linear/GaussianFactorGraph.h>
diff --git a/tests/testBoundingConstraint.cpp b/tests/testBoundingConstraint.cpp
index 65803ecac..b8679d465 100644
--- a/tests/testBoundingConstraint.cpp
+++ b/tests/testBoundingConstraint.cpp
@@ -16,7 +16,7 @@
  */
 
 #include <tests/simulated2DConstraints.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/LevenbergMarquardtOptimizer.h>
 
diff --git a/tests/testDoglegOptimizer.cpp b/tests/testDoglegOptimizer.cpp
index f55bd1b49..8d216724d 100644
--- a/tests/testDoglegOptimizer.cpp
+++ b/tests/testDoglegOptimizer.cpp
@@ -19,7 +19,7 @@
 
 #include <tests/smallExample.h>
 #include <gtsam/nonlinear/DoglegOptimizerImpl.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/linear/JacobianFactor.h>
 #include <gtsam/linear/GaussianBayesTree.h>
 #include <gtsam/base/numericalDerivative.h>
diff --git a/tests/testExtendedKalmanFilter.cpp b/tests/testExtendedKalmanFilter.cpp
index ac3705cab..e1e42af6c 100644
--- a/tests/testExtendedKalmanFilter.cpp
+++ b/tests/testExtendedKalmanFilter.cpp
@@ -18,7 +18,7 @@
 #include <gtsam/slam/BetweenFactor.h>
 #include <gtsam/nonlinear/ExtendedKalmanFilter-inl.h>
 #include <gtsam/nonlinear/NonlinearFactor.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/geometry/Point2.h>
 
 #include <CppUnitLite/TestHarness.h>
diff --git a/tests/testGaussianBayesTree.cpp b/tests/testGaussianBayesTree.cpp
index 653ca0809..fa725a39f 100644
--- a/tests/testGaussianBayesTree.cpp
+++ b/tests/testGaussianBayesTree.cpp
@@ -16,7 +16,7 @@
  */
 
 #include <tests/smallExample.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/linear/GaussianBayesTree.h>
 #include <gtsam/linear/GaussianBayesNet.h>
 #include <gtsam/linear/GaussianConditional.h>
diff --git a/tests/testGaussianFactorGraphB.cpp b/tests/testGaussianFactorGraphB.cpp
index ba889d4e4..850d0eb94 100644
--- a/tests/testGaussianFactorGraphB.cpp
+++ b/tests/testGaussianFactorGraphB.cpp
@@ -16,7 +16,7 @@
  **/
 
 #include <tests/smallExample.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/linear/GaussianBayesNet.h>
 #include <gtsam/linear/GaussianBayesTree.h>
 #include <gtsam/linear/GaussianFactorGraph.h>
diff --git a/tests/testGaussianISAM.cpp b/tests/testGaussianISAM.cpp
index 81c68c106..7f53406c8 100644
--- a/tests/testGaussianISAM.cpp
+++ b/tests/testGaussianISAM.cpp
@@ -18,7 +18,7 @@
 #include <CppUnitLite/TestHarness.h>
 
 #include <tests/smallExample.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/linear/GaussianISAM.h>
 #include <gtsam/inference/Ordering.h>
 
diff --git a/tests/testGaussianJunctionTreeB.cpp b/tests/testGaussianJunctionTreeB.cpp
index 7af67e039..38d64bf63 100644
--- a/tests/testGaussianJunctionTreeB.cpp
+++ b/tests/testGaussianJunctionTreeB.cpp
@@ -26,7 +26,7 @@
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/Values.h>
 #include <gtsam/nonlinear/Ordering.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/linear/GaussianJunctionTree.h>
 #include <gtsam/inference/BayesTree.h>
 #include <gtsam/geometry/Pose2.h>
diff --git a/tests/testIterative.cpp b/tests/testIterative.cpp
index bb4193955..09a3c43e4 100644
--- a/tests/testIterative.cpp
+++ b/tests/testIterative.cpp
@@ -19,7 +19,7 @@
 #include <gtsam/slam/PriorFactor.h>
 #include <gtsam/slam/BetweenFactor.h>
 #include <gtsam/nonlinear/NonlinearEquality.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/linear/iterative.h>
 #include <gtsam/geometry/Pose2.h>
 
diff --git a/tests/testMarginals.cpp b/tests/testMarginals.cpp
index 9e0e76ec7..7f793cf4f 100644
--- a/tests/testMarginals.cpp
+++ b/tests/testMarginals.cpp
@@ -19,7 +19,7 @@
 #include <CppUnitLite/TestHarness.h>
 
 // for all nonlinear keys
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 // for points and poses
 #include <gtsam/geometry/Point2.h>
diff --git a/tests/testNonlinearEquality.cpp b/tests/testNonlinearEquality.cpp
index e31261869..21b2694fb 100644
--- a/tests/testNonlinearEquality.cpp
+++ b/tests/testNonlinearEquality.cpp
@@ -18,7 +18,7 @@
 
 #include <gtsam/slam/PriorFactor.h>
 #include <gtsam/slam/ProjectionFactor.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/nonlinear/NonlinearEquality.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/LevenbergMarquardtOptimizer.h>
diff --git a/tests/testNonlinearFactor.cpp b/tests/testNonlinearFactor.cpp
index f7b212fd7..509b8d890 100644
--- a/tests/testNonlinearFactor.cpp
+++ b/tests/testNonlinearFactor.cpp
@@ -32,7 +32,7 @@
 #include <tests/simulated2D.h>
 #include <gtsam/linear/GaussianFactor.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 using namespace std;
 using namespace gtsam;
diff --git a/tests/testNonlinearFactorGraph.cpp b/tests/testNonlinearFactorGraph.cpp
index ee62c5893..88b2a2b29 100644
--- a/tests/testNonlinearFactorGraph.cpp
+++ b/tests/testNonlinearFactorGraph.cpp
@@ -32,7 +32,7 @@ using namespace boost::assign;
 #include <tests/smallExample.h>
 #include <gtsam/inference/FactorGraph.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 
 using namespace gtsam;
 using namespace example;
diff --git a/tests/testNonlinearISAM.cpp b/tests/testNonlinearISAM.cpp
index c14f4e992..5b510b894 100644
--- a/tests/testNonlinearISAM.cpp
+++ b/tests/testNonlinearISAM.cpp
@@ -10,7 +10,7 @@
 #include <gtsam/nonlinear/NonlinearISAM.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/Values.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/linear/Sampler.h>
 #include <gtsam/geometry/Pose2.h>
 
diff --git a/tests/testNonlinearOptimizer.cpp b/tests/testNonlinearOptimizer.cpp
index bf911dc78..ec035b3be 100644
--- a/tests/testNonlinearOptimizer.cpp
+++ b/tests/testNonlinearOptimizer.cpp
@@ -20,7 +20,7 @@
 #include <gtsam/slam/BetweenFactor.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/Values.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/GaussNewtonOptimizer.h>
 #include <gtsam/nonlinear/DoglegOptimizer.h>
diff --git a/tests/testRot3Optimization.cpp b/tests/testRot3Optimization.cpp
index 866df9ca3..31cf68ebd 100644
--- a/tests/testRot3Optimization.cpp
+++ b/tests/testRot3Optimization.cpp
@@ -24,7 +24,7 @@
 #include <gtsam/geometry/Rot3.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/nonlinear/GaussNewtonOptimizer.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/slam/BetweenFactor.h>
 #include <gtsam/slam/PriorFactor.h>
 
diff --git a/tests/testSerializationSLAM.cpp b/tests/testSerializationSLAM.cpp
index 8c0254a4e..ecf82d1bd 100644
--- a/tests/testSerializationSLAM.cpp
+++ b/tests/testSerializationSLAM.cpp
@@ -33,7 +33,7 @@
 #include <gtsam/slam/RangeFactor.h>
 #include <gtsam/slam/StereoFactor.h>
 #include <gtsam/nonlinear/NonlinearEquality.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/linear/GaussianISAM.h>
 #include <gtsam/base/LieVector.h>
 #include <gtsam/base/LieMatrix.h>
diff --git a/tests/testSimulated2DOriented.cpp b/tests/testSimulated2DOriented.cpp
index 9e82bd2a7..cf505c485 100644
--- a/tests/testSimulated2DOriented.cpp
+++ b/tests/testSimulated2DOriented.cpp
@@ -18,7 +18,7 @@
 
 #include <tests/simulated2D.h>
 #include <tests/simulated2DOriented.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/base/Testable.h>
 #include <gtsam/base/numericalDerivative.h>
 
diff --git a/tests/testSimulated3D.cpp b/tests/testSimulated3D.cpp
index 9599dfbf3..dcfcc735b 100644
--- a/tests/testSimulated3D.cpp
+++ b/tests/testSimulated3D.cpp
@@ -16,7 +16,7 @@
  **/
 
 #include <tests/simulated3D.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/geometry/Pose3.h>
 #include <gtsam/base/Testable.h>
 #include <gtsam/base/numericalDerivative.h>
diff --git a/tests/testSubgraphPreconditioner.cpp b/tests/testSubgraphPreconditioner.cpp
index 679bdcf4b..352440ef5 100644
--- a/tests/testSubgraphPreconditioner.cpp
+++ b/tests/testSubgraphPreconditioner.cpp
@@ -20,7 +20,7 @@
 #if 0
 
 #include <tests/smallExample.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/linear/iterative.h>
 #include <gtsam/linear/GaussianFactorGraph.h>
 #include <gtsam/linear/SubgraphPreconditioner.h>
diff --git a/tests/testSubgraphSolver.cpp b/tests/testSubgraphSolver.cpp
index b8a0346de..f5d0384f2 100644
--- a/tests/testSubgraphSolver.cpp
+++ b/tests/testSubgraphSolver.cpp
@@ -20,7 +20,7 @@
 #if 0
 
 #include <tests/smallExample.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/linear/GaussianBayesNet.h>
 #include <gtsam/linear/iterative.h>
 #include <gtsam/linear/GaussianFactorGraph.h>
diff --git a/tests/timeIncremental.cpp b/tests/timeIncremental.cpp
index 3a8f26b09..6f2909b7a 100644
--- a/tests/timeIncremental.cpp
+++ b/tests/timeIncremental.cpp
@@ -20,7 +20,7 @@
 #include <gtsam/slam/PriorFactor.h>
 #include <gtsam/slam/BetweenFactor.h>
 #include <gtsam/slam/BearingRangeFactor.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/nonlinear/ISAM2.h>
 #include <gtsam/nonlinear/Marginals.h>
 
diff --git a/tests/timeiSAM2Chain.cpp b/tests/timeiSAM2Chain.cpp
index 9ed18a1ef..d15ccfaf4 100644
--- a/tests/timeiSAM2Chain.cpp
+++ b/tests/timeiSAM2Chain.cpp
@@ -19,7 +19,7 @@
 #include <gtsam/geometry/Pose2.h>
 #include <gtsam/slam/PriorFactor.h>
 #include <gtsam/slam/BetweenFactor.h>
-#include <gtsam/nonlinear/Symbol.h>
+#include <gtsam/inference/Symbol.h>
 #include <gtsam/nonlinear/ISAM2.h>
 #include <gtsam/nonlinear/Marginals.h>