diff --git a/include/ceres/dynamic_autodiff_cost_function.h b/include/ceres/dynamic_autodiff_cost_function.h
index e6d2611..1cece2c 100644
--- a/include/ceres/dynamic_autodiff_cost_function.h
+++ b/include/ceres/dynamic_autodiff_cost_function.h
@@ -28,7 +28,21 @@
 //
 // Author: sameeragarwal@google.com (Sameer Agarwal)
 //         mierle@gmail.com (Keir Mierle)
-//
+
+#ifndef CERES_PUBLIC_DYNAMIC_AUTODIFF_COST_FUNCTION_H_
+#define CERES_PUBLIC_DYNAMIC_AUTODIFF_COST_FUNCTION_H_
+
+#include <cmath>
+#include <numeric>
+#include <vector>
+
+#include "ceres/dynamic_cost_function.h"
+#include "ceres/internal/scoped_ptr.h"
+#include "ceres/jet.h"
+#include "glog/logging.h"
+
+namespace ceres {
+
 // This autodiff implementation differs from the one found in
 // autodiff_cost_function.h by supporting autodiff on cost functions
 // with variable numbers of parameters with variable sizes. With the
@@ -60,37 +74,14 @@
 // default, controlled by the Stride template parameter) with each
 // pass. There is a tradeoff with the size of the passes; you may want
 // to experiment with the stride.
-
-#ifndef CERES_PUBLIC_DYNAMIC_AUTODIFF_COST_FUNCTION_H_
-#define CERES_PUBLIC_DYNAMIC_AUTODIFF_COST_FUNCTION_H_
-
-#include <cmath>
-#include <numeric>
-#include <vector>
-
-#include "ceres/cost_function.h"
-#include "ceres/internal/scoped_ptr.h"
-#include "ceres/jet.h"
-#include "glog/logging.h"
-
-namespace ceres {
-
 template <typename CostFunctor, int Stride = 4>
-class DynamicAutoDiffCostFunction : public CostFunction {
+class DynamicAutoDiffCostFunction : public DynamicCostFunction {
  public:
   explicit DynamicAutoDiffCostFunction(CostFunctor* functor)
     : functor_(functor) {}
 
   virtual ~DynamicAutoDiffCostFunction() {}
 
-  void AddParameterBlock(int size) {
-    mutable_parameter_block_sizes()->push_back(size);
-  }
-
-  void SetNumResiduals(int num_residuals) {
-    set_num_residuals(num_residuals);
-  }
-
   virtual bool Evaluate(double const* const* parameters,
                         double* residuals,
                         double** jacobians) const {
diff --git a/include/ceres/dynamic_cost_function.h b/include/ceres/dynamic_cost_function.h
new file mode 100644
index 0000000..6c0aa31
--- /dev/null
+++ b/include/ceres/dynamic_cost_function.h
@@ -0,0 +1,56 @@
+// Ceres Solver - A fast non-linear least squares minimizer
+// Copyright 2016 Google Inc. All rights reserved.
+// http://ceres-solver.org/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// * Redistributions of source code must retain the above copyright notice,
+//   this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above copyright notice,
+//   this list of conditions and the following disclaimer in the documentation
+//   and/or other materials provided with the distribution.
+// * Neither the name of Google Inc. nor the names of its contributors may be
+//   used to endorse or promote products derived from this software without
+//   specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+// POSSIBILITY OF SUCH DAMAGE.
+//
+// Author: sameeragarwal@google.com (Sameer Agarwal)
+
+#ifndef CERES_PUBLIC_DYNAMIC_COST_FUNCTION_H_
+#define CERES_PUBLIC_DYNAMIC_COST_FUNCTION_H_
+
+#include "ceres/cost_function.h"
+
+namespace ceres {
+
+// A common base class for DynamicAutoDiffCostFunction and
+// DynamicNumericDiffCostFunction which depend on methods that can add
+// parameter blocks and set the number of residuals at run time.
+class CERES_EXPORT DynamicCostFunction : public CostFunction {
+ public:
+  ~DynamicCostFunction() {}
+
+  virtual void AddParameterBlock(int size) {
+    mutable_parameter_block_sizes()->push_back(size);
+  }
+
+  virtual void SetNumResiduals(int num_residuals) {
+    set_num_residuals(num_residuals);
+  }
+};
+
+}  // namespace ceres
+
+#endif  // CERES_PUBLIC_DYNAMIC_COST_FUNCTION_H_
diff --git a/include/ceres/dynamic_cost_function_to_functor.h b/include/ceres/dynamic_cost_function_to_functor.h
index 9339a50..31280dc 100644
--- a/include/ceres/dynamic_cost_function_to_functor.h
+++ b/include/ceres/dynamic_cost_function_to_functor.h
@@ -28,7 +28,20 @@
 //
 // Author: sameeragarwal@google.com (Sameer Agarwal)
 //         dgossow@google.com (David Gossow)
-//
+
+#ifndef CERES_PUBLIC_DYNAMIC_COST_FUNCTION_TO_FUNCTOR_H_
+#define CERES_PUBLIC_DYNAMIC_COST_FUNCTION_TO_FUNCTOR_H_
+
+#include <numeric>
+#include <vector>
+
+#include "ceres/dynamic_cost_function.h"
+#include "ceres/internal/fixed_array.h"
+#include "ceres/internal/port.h"
+#include "ceres/internal/scoped_ptr.h"
+
+namespace ceres {
+
 // DynamicCostFunctionToFunctor allows users to use CostFunction
 // objects in templated functors which are to be used for automatic
 // differentiation. It works similar to CostFunctionToFunctor, with the
@@ -87,20 +100,6 @@
 //  private:
 //   DynamicCostFunctionToFunctor intrinsic_projection_;
 // };
-
-#ifndef CERES_PUBLIC_DYNAMIC_COST_FUNCTION_TO_FUNCTOR_H_
-#define CERES_PUBLIC_DYNAMIC_COST_FUNCTION_TO_FUNCTOR_H_
-
-#include <numeric>
-#include <vector>
-
-#include "ceres/cost_function.h"
-#include "ceres/internal/fixed_array.h"
-#include "ceres/internal/port.h"
-#include "ceres/internal/scoped_ptr.h"
-
-namespace ceres {
-
 class DynamicCostFunctionToFunctor {
  public:
   // Takes ownership of cost_function.
diff --git a/include/ceres/dynamic_numeric_diff_cost_function.h b/include/ceres/dynamic_numeric_diff_cost_function.h
index 5770946..a011ac3 100644
--- a/include/ceres/dynamic_numeric_diff_cost_function.h
+++ b/include/ceres/dynamic_numeric_diff_cost_function.h
@@ -30,7 +30,23 @@
 //         sameeragarwal@google.com (Sameer Agarwal)
 //         thadh@gmail.com (Thad Hughes)
 //         tbennun@gmail.com (Tal Ben-Nun)
-//
+
+#ifndef CERES_PUBLIC_DYNAMIC_NUMERIC_DIFF_COST_FUNCTION_H_
+#define CERES_PUBLIC_DYNAMIC_NUMERIC_DIFF_COST_FUNCTION_H_
+
+#include <cmath>
+#include <numeric>
+#include <vector>
+
+#include "ceres/dynamic_cost_function.h"
+#include "ceres/internal/scoped_ptr.h"
+#include "ceres/internal/eigen.h"
+#include "ceres/internal/numeric_diff.h"
+#include "ceres/numeric_diff_options.h"
+#include "glog/logging.h"
+
+namespace ceres {
+
 // This numeric diff implementation differs from the one found in
 // numeric_diff_cost_function.h by supporting numericdiff on cost
 // functions with variable numbers of parameters with variable
@@ -56,25 +72,8 @@
 //   cost_function.AddParameterBlock(5);
 //   cost_function.AddParameterBlock(10);
 //   cost_function.SetNumResiduals(21);
-
-#ifndef CERES_PUBLIC_DYNAMIC_NUMERIC_DIFF_COST_FUNCTION_H_
-#define CERES_PUBLIC_DYNAMIC_NUMERIC_DIFF_COST_FUNCTION_H_
-
-#include <cmath>
-#include <numeric>
-#include <vector>
-
-#include "ceres/cost_function.h"
-#include "ceres/internal/scoped_ptr.h"
-#include "ceres/internal/eigen.h"
-#include "ceres/internal/numeric_diff.h"
-#include "ceres/numeric_diff_options.h"
-#include "glog/logging.h"
-
-namespace ceres {
-
 template <typename CostFunctor, NumericDiffMethodType method = CENTRAL>
-class DynamicNumericDiffCostFunction : public CostFunction {
+class DynamicNumericDiffCostFunction : public DynamicCostFunction {
  public:
   explicit DynamicNumericDiffCostFunction(
       const CostFunctor* functor,
@@ -91,14 +90,6 @@
     }
   }
 
-  void AddParameterBlock(int size) {
-    mutable_parameter_block_sizes()->push_back(size);
-  }
-
-  void SetNumResiduals(int num_residuals) {
-    set_num_residuals(num_residuals);
-  }
-
   virtual bool Evaluate(double const* const* parameters,
                         double* residuals,
                         double** jacobians) const {