diff --git a/internal/ceres/compressed_row_jacobian_writer.h b/internal/ceres/compressed_row_jacobian_writer.h
index c103165..935e650 100644
--- a/internal/ceres/compressed_row_jacobian_writer.h
+++ b/internal/ceres/compressed_row_jacobian_writer.h
@@ -39,6 +39,7 @@
 namespace ceres {
 namespace internal {
 
+class CompressedRowSparseMatrix;
 class Program;
 class SparseMatrix;
 
@@ -49,6 +50,36 @@
     : program_(program) {
   }
 
+  // `PopulateJacobianRowAndColumnBlockVectors` sets `col_blocks` and
+  // `row_blocks` for a `CompressedRowSparseMatrix`, based on the parameter
+  // block sizes and residual sizes respectively from the program. This is
+  // useful when Solver::Options::use_block_amd = true;
+  //
+  // This function is static so that it is available to other jacobian
+  // writers which use `CompressedRowSparseMatrix` (or derived types).
+  // (Jacobian writers do not fall under any type hierarchy; they only
+  // have to provide an interface as specified in program_evaluator.h).
+  static void PopulateJacobianRowAndColumnBlockVectors(
+      const Program* program,
+      CompressedRowSparseMatrix* jacobian);
+
+  // It is necessary to determine the order of the jacobian blocks before
+  // copying them into a `CompressedRowSparseMatrix` (or derived type).
+  // Just because a cost function uses parameter blocks 1 after 2 in its
+  // arguments does not mean that the block 1 occurs before block 2 in the
+  // column layout of the jacobian. Thus, `GetOrderedParameterBlocks`
+  // determines the order by sorting the jacobian blocks by their position in
+  // the state vector.
+  //
+  // This function is static so that it is available to other jacobian
+  // writers which use `CompressedRowSparseMatrix` (or derived types).
+  // (Jacobian writers do not fall under any type hierarchy; they only
+  // have to provide an interface as specified in program_evaluator.h).
+  static void GetOrderedParameterBlocks(
+      const Program* program,
+      int residual_id,
+      vector<pair<int, int> >* evaluated_jacobian_blocks);
+
   // JacobianWriter interface.
 
   // Since the compressed row matrix has different layout than that assumed by