diff --git a/examples/InverseKinematicsExampleExpressions.cpp b/examples/InverseKinematicsExampleExpressions.cpp
index 9da1c62c0..1df83d9a1 100644
--- a/examples/InverseKinematicsExampleExpressions.cpp
+++ b/examples/InverseKinematicsExampleExpressions.cpp
@@ -22,7 +22,6 @@
 #include <gtsam/nonlinear/Marginals.h>
 #include <gtsam/nonlinear/expressions.h>
 #include <gtsam/slam/BetweenFactor.h>
-#include <gtsam/nonlinear/PriorFactor.h>
 #include <gtsam/slam/expressions.h>
 
 #include <cmath>
diff --git a/examples/Pose2SLAMExampleExpressions.cpp b/examples/Pose2SLAMExampleExpressions.cpp
index 3760d0dd0..c35b9bc45 100644
--- a/examples/Pose2SLAMExampleExpressions.cpp
+++ b/examples/Pose2SLAMExampleExpressions.cpp
@@ -21,7 +21,6 @@
 #include <gtsam/nonlinear/ExpressionFactorGraph.h>
 
 // For an explanation of headers below, please see Pose2SLAMExample.cpp
-#include <gtsam/nonlinear/PriorFactor.h>
 #include <gtsam/slam/BetweenFactor.h>
 #include <gtsam/geometry/Pose2.h>
 #include <gtsam/nonlinear/GaussNewtonOptimizer.h>
diff --git a/examples/Pose3SLAMExample_changeKeys.cpp b/examples/Pose3SLAMExample_changeKeys.cpp
index b72acd30d..abadce975 100644
--- a/examples/Pose3SLAMExample_changeKeys.cpp
+++ b/examples/Pose3SLAMExample_changeKeys.cpp
@@ -19,7 +19,6 @@
 
 #include <gtsam/slam/dataset.h>
 #include <gtsam/slam/BetweenFactor.h>
-#include <gtsam/nonlinear/PriorFactor.h>
 #include <fstream>
 
 using namespace std;
diff --git a/examples/SimpleRotation.cpp b/examples/SimpleRotation.cpp
index 916238a28..c444c85aa 100644
--- a/examples/SimpleRotation.cpp
+++ b/examples/SimpleRotation.cpp
@@ -32,8 +32,8 @@
 
 // In GTSAM, measurement functions are represented as 'factors'. Several common factors
 // have been provided with the library for solving robotics/SLAM/Bundle Adjustment problems.
-// We will apply a simple prior on the rotation
-#include <gtsam/nonlinear/PriorFactor.h>
+// We will apply a simple prior on the rotation. We do so via the `addPrior` convenience
+// method in NonlinearFactorGraph.
 
 // When the factors are created, we will add them to a Factor Graph. As the factors we are using
 // are nonlinear factors, we will need a Nonlinear Factor Graph.
@@ -78,7 +78,6 @@ int main() {
   prior.print("goal angle");
   noiseModel::Isotropic::shared_ptr model = noiseModel::Isotropic::Sigma(1, 1 * degree);
   Symbol key('x',1);
-  PriorFactor<Rot2> factor(key, prior, model);
 
   /**
    *    Step 2: Create a graph container and add the factor to it
@@ -90,7 +89,7 @@ int main() {
    * many more factors would be added.
    */
   NonlinearFactorGraph graph;
-  graph.push_back(factor);
+  graph.addPrior(key, prior, model);
   graph.print("full graph");
 
   /**
diff --git a/gtsam/geometry/triangulation.h b/gtsam/geometry/triangulation.h
index 087d7c86a..6c0f9c8f4 100644
--- a/gtsam/geometry/triangulation.h
+++ b/gtsam/geometry/triangulation.h
@@ -22,7 +22,6 @@
 #include <gtsam/geometry/CameraSet.h>
 #include <gtsam/geometry/Pose2.h>
 #include <gtsam/slam/TriangulationFactor.h>
-#include <gtsam/nonlinear/PriorFactor.h>
 #include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/inference/Symbol.h>
 
diff --git a/gtsam/slam/tests/testOrientedPlane3Factor.cpp b/gtsam/slam/tests/testOrientedPlane3Factor.cpp
index c903d5232..81f67f1ee 100644
--- a/gtsam/slam/tests/testOrientedPlane3Factor.cpp
+++ b/gtsam/slam/tests/testOrientedPlane3Factor.cpp
@@ -17,7 +17,6 @@
  */
 
 #include <gtsam/slam/OrientedPlane3Factor.h>
-#include <gtsam/nonlinear/PriorFactor.h>
 #include <gtsam/nonlinear/ISAM2.h>
 #include <gtsam/inference/Symbol.h>
 #include <gtsam/base/numericalDerivative.h>
@@ -49,10 +48,9 @@ TEST (OrientedPlane3Factor, lm_translation_error) {
   Pose3 init_pose(Rot3::Ypr(0.0, 0.0, 0.0), Point3(0.0, 0.0, 0.0));
   Vector sigmas(6);
   sigmas << 0.001, 0.001, 0.001, 0.001, 0.001, 0.001;
-  PriorFactor<Pose3> pose_prior(init_sym, init_pose,
-      noiseModel::Diagonal::Sigmas(sigmas));
+  new_graph.addPrior(
+      init_sym, init_pose, noiseModel::Diagonal::Sigmas(sigmas));
   new_values.insert(init_sym, init_pose);
-  new_graph.add(pose_prior);
 
   // Add two landmark measurements, differing in range
   new_values.insert(lm_sym, test_lm0);
@@ -94,11 +92,10 @@ TEST (OrientedPlane3Factor, lm_rotation_error) {
   // Init pose and prior.  Pose Prior is needed since a single plane measurement does not fully constrain the pose
   Symbol init_sym('x', 0);
   Pose3 init_pose(Rot3::Ypr(0.0, 0.0, 0.0), Point3(0.0, 0.0, 0.0));
-  PriorFactor<Pose3> pose_prior(init_sym, init_pose,
+  new_graph.addPrior(init_sym, init_pose,
       noiseModel::Diagonal::Sigmas(
           (Vector(6) << 0.001, 0.001, 0.001, 0.001, 0.001, 0.001).finished()));
   new_values.insert(init_sym, init_pose);
-  new_graph.add(pose_prior);
 
 //  // Add two landmark measurements, differing in angle
   new_values.insert(lm_sym, test_lm0);
diff --git a/gtsam_unstable/slam/tests/testMultiProjectionFactor.cpp b/gtsam_unstable/slam/tests/testMultiProjectionFactor.cpp
index 2ae1b1d5b..141a50465 100644
--- a/gtsam_unstable/slam/tests/testMultiProjectionFactor.cpp
+++ b/gtsam_unstable/slam/tests/testMultiProjectionFactor.cpp
@@ -16,7 +16,6 @@
  *  @date Nov 2009
  */
 
-#include <gtsam/nonlinear/PriorFactor.h>
 #include <gtsam/slam/BetweenFactor.h>
 #include <gtsam/slam/ProjectionFactor.h>
 #include <gtsam_unstable/slam/MultiProjectionFactor.h>