diff --git a/internal/ceres/problem_impl.h b/internal/ceres/problem_impl.h
index 82a1956..536e73a 100644
--- a/internal/ceres/problem_impl.h
+++ b/internal/ceres/problem_impl.h
@@ -118,6 +118,10 @@
   void AddParameterBlock(double* values,
                          int size,
                          LocalParameterization* local_parameterization);
+
+  void RemoveResidualBlock(ResidualBlock* residual_block);
+  void RemoveParameterBlock(double* values);
+
   void SetParameterBlockConstant(double* values);
   void SetParameterBlockVariable(double* values);
   void SetParameterization(double* values,
@@ -135,12 +139,33 @@
  private:
   ParameterBlock* InternalAddParameterBlock(double* values, int size);
 
+  // Delete the arguments in question. These differ from the Remove* functions
+  // in that they do not clean up references to the block to delete; they
+  // merely delete them.
+  template<typename Block>
+  void DeleteBlockInVector(vector<Block*>* mutable_blocks,
+                           Block* block_to_remove);
+  void DeleteBlock(ResidualBlock* residual_block);
+  void DeleteBlock(ParameterBlock* parameter_block);
+
   const Problem::Options options_;
 
   // The mapping from user pointers to parameter blocks.
   map<double*, ParameterBlock*> parameter_block_map_;
 
+  // The actual parameter and residual blocks.
   internal::scoped_ptr<internal::Program> program_;
+
+  // When removing residual and parameter blocks, cost/loss functions and
+  // parameterizations have ambiguous ownership. Instead of scanning the entire
+  // problem to see if the cost/loss/parameterization is shared with other
+  // residual or parameter blocks, buffer them until destruction.
+  //
+  // TODO(keir): See if it makes sense to use sets instead.
+  vector<CostFunction*> cost_functions_to_delete_;
+  vector<LossFunction*> loss_functions_to_delete_;
+  vector<LocalParameterization*> local_parameterizations_to_delete_;
+
   CERES_DISALLOW_COPY_AND_ASSIGN(ProblemImpl);
 };