diff --git a/nonlinear/Ordering.cpp b/nonlinear/Ordering.cpp
index 22b83756b..8afd243de 100644
--- a/nonlinear/Ordering.cpp
+++ b/nonlinear/Ordering.cpp
@@ -15,6 +15,13 @@ using namespace std;
 
 namespace gtsam {
 
+/* ************************************************************************* */
+Ordering::Ordering(const std::list<Symbol> & L):nVars_(0) {
+	int i = 0;
+	BOOST_FOREACH( const Symbol& s, L )
+	  insert(s, i++) ;
+}
+
 /* ************************************************************************* */
 void Ordering::permuteWithInverse(const Permutation& inversePermutation) {
   BOOST_FOREACH(Ordering::value_type& key_order, *this) {
diff --git a/nonlinear/Ordering.h b/nonlinear/Ordering.h
index 7fb97496d..f58b78717 100644
--- a/nonlinear/Ordering.h
+++ b/nonlinear/Ordering.h
@@ -38,10 +38,7 @@ public:
   typedef Map::const_iterator const_iterator;
 
   Ordering() : nVars_(0) {}
-  Ordering(const std::list<Symbol> & L):nVars_(0) {
-	  int i = 0;
-	  BOOST_FOREACH( const Symbol& s, L) insert(s, i++) ;
-  }
+  Ordering(const std::list<Symbol> & L) ;
 
   /** One greater than the maximum ordering index. */
   Index nVars() const { return nVars_; }