diff --git a/gtsam/nonlinear/Expression-inl.h b/gtsam/nonlinear/Expression-inl.h
index b3ead11c4..06a25ac23 100644
--- a/gtsam/nonlinear/Expression-inl.h
+++ b/gtsam/nonlinear/Expression-inl.h
@@ -164,7 +164,7 @@ T Expression<T>::value(const Values& values, const FastVector<Key>& keys,
   static const int Dim = traits<T>::dimension;
   VerticalBlockMatrix Ab(dims, Dim);
   Ab.matrix().setZero();
-  JacobianMap jacobianMap(keys, Ab);
+  internal::JacobianMap jacobianMap(keys, Ab);
 
   // Call unsafe version
   T result = value(values, jacobianMap);
@@ -184,7 +184,7 @@ T Expression<T>::traceExecution(const Values& values,
 }
 
 template<typename T>
-T Expression<T>::value(const Values& values, JacobianMap& jacobians) const {
+T Expression<T>::value(const Values& values, internal::JacobianMap& jacobians) const {
   // The following piece of code is absolutely crucial for performance.
   // We allocate a block of memory on the stack, which can be done at runtime
   // with modern C++ compilers. The traceExecution then fills this memory
diff --git a/gtsam/nonlinear/Expression.h b/gtsam/nonlinear/Expression.h
index 2c503dce9..faa884562 100644
--- a/gtsam/nonlinear/Expression.h
+++ b/gtsam/nonlinear/Expression.h
@@ -19,7 +19,7 @@
 
 #pragma once
 
-#include <gtsam/nonlinear/JacobianMap.h>
+#include <gtsam/nonlinear/internal/JacobianMap.h>
 #include <gtsam/inference/Symbol.h>
 #include <gtsam/base/OptionalJacobian.h>
 
@@ -178,7 +178,7 @@ private:
       void* traceStorage) const;
 
   /// brief Return value and derivatives, reverse AD version
-  T value(const Values& values, JacobianMap& jacobians) const;
+  T value(const Values& values, internal::JacobianMap& jacobians) const;
 
   // be very selective on who can access these private methods:
   friend class ExpressionFactor<T>;
diff --git a/gtsam/nonlinear/ExpressionFactor.h b/gtsam/nonlinear/ExpressionFactor.h
index 4e0467a3b..afb487ff4 100644
--- a/gtsam/nonlinear/ExpressionFactor.h
+++ b/gtsam/nonlinear/ExpressionFactor.h
@@ -89,7 +89,7 @@ public:
 
     // Wrap keys and VerticalBlockMatrix into structure passed to expression_
     VerticalBlockMatrix& Ab = factor->matrixObject();
-    JacobianMap jacobianMap(keys_, Ab);
+    internal::JacobianMap jacobianMap(keys_, Ab);
 
     // Zero out Jacobian so we can simply add to it
     Ab.matrix().setZero();
diff --git a/gtsam/nonlinear/internal/CallRecord.h b/gtsam/nonlinear/internal/CallRecord.h
index 88ba0fb2d..50d08cb8e 100644
--- a/gtsam/nonlinear/internal/CallRecord.h
+++ b/gtsam/nonlinear/internal/CallRecord.h
@@ -20,7 +20,7 @@
 
 #pragma once
 
-#include <gtsam/nonlinear/JacobianMap.h>
+#include <gtsam/nonlinear/internal/JacobianMap.h>
 #include <boost/mpl/transform.hpp>
 
 namespace gtsam {
diff --git a/gtsam/nonlinear/internal/ExecutionTrace.h b/gtsam/nonlinear/internal/ExecutionTrace.h
index ca7d78d81..37ce4dfd5 100644
--- a/gtsam/nonlinear/internal/ExecutionTrace.h
+++ b/gtsam/nonlinear/internal/ExecutionTrace.h
@@ -18,7 +18,7 @@
 
 #pragma once
 
-#include <gtsam/nonlinear/JacobianMap.h>
+#include <gtsam/nonlinear/internal/JacobianMap.h>
 #include <gtsam/inference/Key.h>
 #include <gtsam/base/Manifold.h>
 
diff --git a/gtsam/nonlinear/JacobianMap.h b/gtsam/nonlinear/internal/JacobianMap.h
similarity index 97%
rename from gtsam/nonlinear/JacobianMap.h
rename to gtsam/nonlinear/internal/JacobianMap.h
index 43e22fc16..f4d2e9565 100644
--- a/gtsam/nonlinear/JacobianMap.h
+++ b/gtsam/nonlinear/internal/JacobianMap.h
@@ -23,6 +23,7 @@
 #include <gtsam/base/VerticalBlockMatrix.h>
 
 namespace gtsam {
+namespace internal {
 
 // A JacobianMap is the primary mechanism by which derivatives are returned.
 // Expressions are designed to write their derivatives into an already allocated
@@ -48,5 +49,6 @@ public:
   }
 };
 
+} // namespace internal
 } // namespace gtsam
 
diff --git a/gtsam/nonlinear/tests/testCallRecord.cpp b/gtsam/nonlinear/tests/testCallRecord.cpp
index 09099ba1b..208f0b284 100644
--- a/gtsam/nonlinear/tests/testCallRecord.cpp
+++ b/gtsam/nonlinear/tests/testCallRecord.cpp
@@ -80,13 +80,13 @@ struct Record: public internal::CallRecordImplementor<Record, Cols> {
   }
   void print(const std::string& indent) const {
   }
-  void startReverseAD4(JacobianMap& jacobians) const {
+  void startReverseAD4(internal::JacobianMap& jacobians) const {
   }
 
   mutable CallConfig cc;
  private:
   template<typename SomeMatrix>
-  void reverseAD4(const SomeMatrix & dFdT, JacobianMap& jacobians) const {
+  void reverseAD4(const SomeMatrix & dFdT, internal::JacobianMap& jacobians) const {
     cc.compTimeRows = SomeMatrix::RowsAtCompileTime;
     cc.compTimeCols = SomeMatrix::ColsAtCompileTime;
     cc.runTimeRows = dFdT.rows();
@@ -97,7 +97,7 @@ struct Record: public internal::CallRecordImplementor<Record, Cols> {
   friend struct internal::CallRecordImplementor;
 };
 
-JacobianMap & NJM= *static_cast<JacobianMap *>(NULL);
+internal::JacobianMap & NJM= *static_cast<internal::JacobianMap *>(NULL);
 
 /* ************************************************************************* */
 typedef Eigen::Matrix<double, Eigen::Dynamic, Cols> DynRowMat;