diff --git a/include/IECoreRI/private/SXRendererImplementation.h b/include/IECoreRI/private/SXRendererImplementation.h
index 67efdab6a3..5c8e88ea54 100644
--- a/include/IECoreRI/private/SXRendererImplementation.h
+++ b/include/IECoreRI/private/SXRendererImplementation.h
@@ -139,6 +139,8 @@ class SXRendererImplementation : public IECore::Renderer
 			SxShader imagerShader;
 			SXExecutor::ShaderVector coshaders;
 			SXExecutor::ShaderVector lights;
+			
+			Imath::M44f transform;
 		};
 		typedef std::stack<State> StateStack;
 		
diff --git a/src/IECoreRI/SXRendererImplementation.cpp b/src/IECoreRI/SXRendererImplementation.cpp
index 6cdeaffec2..9582110434 100644
--- a/src/IECoreRI/SXRendererImplementation.cpp
+++ b/src/IECoreRI/SXRendererImplementation.cpp
@@ -34,6 +34,7 @@
 
 #include "IECoreRI/private/SXRendererImplementation.h"
 #include "IECoreRI/SXExecutor.h"
+#include "IECoreRI/Convert.h"
 
 #include "IECore/MessageHandler.h"
 #include "IECore/Shader.h"
@@ -41,7 +42,6 @@
 #include "IECore/SplineData.h"
 #include "IECore/MatrixAlgo.h"
 #include "IECore/Transform.h"
-#include "IECore/MatrixTransform.h"
 #include "IECore/Group.h"
 
 #include "boost/algorithm/string/case_conv.hpp"
@@ -227,17 +227,25 @@ void IECoreRI::SXRendererImplementation::worldEnd()
 
 void IECoreRI::SXRendererImplementation::transformBegin()
 {
-	msg( Msg::Warning, "IECoreRI::SXRendererImplementation::transformBegin", "Not implemented" );
+	// New push state onto the stack: deep copy flag is false, so we don't create a new SxContext, which will swallow up any
+	// coordinate systems declared before transformEnd():
+	m_stateStack.push( State( m_stateStack.top(), false ) );
 }
 
 void IECoreRI::SXRendererImplementation::transformEnd()
 {
-	msg( Msg::Warning, "IECoreRI::SXRendererImplementation::transformEnd", "Not implemented" );
+	unsigned minimumStack = m_inWorld ? 2 : 1;
+	if( m_stateStack.size() <= minimumStack )
+	{
+		IECore::msg( IECore::Msg::Error, "IECoreRI::SXRenderer::transformEnd", "No matching transformBegin." );
+		return;
+	}
+	m_stateStack.pop();
 }
 
 void IECoreRI::SXRendererImplementation::setTransform( const Imath::M44f &m )
 {
-	msg( Msg::Warning, "IECoreRI::SXRendererImplementation::setTransform", "Not implemented" );
+	m_stateStack.top().transform = m;
 }
 
 void IECoreRI::SXRendererImplementation::setTransform( const std::string &coordinateSystem )
@@ -247,7 +255,7 @@ void IECoreRI::SXRendererImplementation::setTransform( const std::string &coordi
 
 Imath::M44f IECoreRI::SXRendererImplementation::getTransform() const
 {
-	return getTransform( "object" );
+	return m_stateStack.top().transform;
 }
 
 Imath::M44f IECoreRI::SXRendererImplementation::getTransform( const std::string &coordinateSystem ) const
@@ -258,12 +266,15 @@ Imath::M44f IECoreRI::SXRendererImplementation::getTransform( const std::string
 
 void IECoreRI::SXRendererImplementation::concatTransform( const Imath::M44f &m )
 {
-	msg( Msg::Warning, "IECoreRI::SXRendererImplementation::concatTransform", "Not implemented" );
+	m_stateStack.top().transform = m * m_stateStack.top().transform;
 }
 
 void IECoreRI::SXRendererImplementation::coordinateSystem( const std::string &name )
 {
-	msg( Msg::Warning, "IECoreRI::SXRendererImplementation::coordinateSystem", "Not implemented" );
+	M44f m = m_stateStack.top().transform.transposed();
+	RtMatrix mm;
+	convert( m, mm );
+	SxDefineSpace ( m_stateStack.top().context.get(), name.c_str(), (RtFloat*)&mm[0][0] );
 }
 
 //////////////////////////////////////////////////////////////////////////////////////////
diff --git a/test/IECoreRI/SXRendererTest.py b/test/IECoreRI/SXRendererTest.py
index 60f160e984..eb7a59da9e 100644
--- a/test/IECoreRI/SXRendererTest.py
+++ b/test/IECoreRI/SXRendererTest.py
@@ -127,7 +127,7 @@ def __assertVectorDataAlmostEqual( self, data1, data2 ) :
 		else : 
 			for i in range( 0, len( data1 ) ) :
 				self.assertAlmostEqual( data1[i], data2[i], 6 )
-		
+	
 	def test( self ) :
 
 		r = IECoreRI.SXRenderer()
@@ -901,7 +901,42 @@ def testUserOptions( self ):
 		s = r.shade( points )
 		self.assertEqual( s["Ci"][0], IECore.Color3f( 1,1,1 ) )
 		
-					
+	
+	def testCoordinateSystems( self ):
+		
+		self.assertEqual( os.system( "shaderdl -Irsl -o test/IECoreRI/shaders/sxCoordSystemTest.sdl test/IECoreRI/shaders/sxCoordSystemTest.sl" ), 0 )
+		
+		points = self.__rectanglePoints( IECore.Box2i( IECore.V2i( 0 ), IECore.V2i( 1 ) ) )
+		
+		r = IECoreRI.SXRenderer()
+		
+		r.shader( "surface", "test/IECoreRI/shaders/sxCoordSystemTest.sdl", { "coordSysName" : IECore.StringData( "test1" ) } )
+		
+		r.transformBegin()
+		r.setTransform( IECore.M44f.createTranslated( IECore.V3f(0,0,2) ) )
+		r.coordinateSystem( "test1" )
+		r.transformEnd()
+		
+		r.transformBegin()
+		r.setTransform( IECore.M44f.createRotated( IECore.V3f(1,0,0) ) )
+		r.concatTransform( IECore.M44f.createTranslated( IECore.V3f(0,0,2) ) )
+		r.coordinateSystem( "test2" )
+		r.transformEnd()
+		
+		s1 = r.shade( points )
+		for i in range( len( s1["Ci"] ) ):
+			self.assertEqual( points["P"][i] + IECore.V3f(0,0,2), IECore.V3f( s1["Ci"][i][0], s1["Ci"][i][1], s1["Ci"][i][2] ) )
+		
+		r.shader( "surface", "test/IECoreRI/shaders/sxCoordSystemTest.sdl", { "coordSysName" : IECore.StringData( "test2" ) } )
+		s2 = r.shade( points )
+		for i in range( len( s2["Ci"] ) ):
+			shaderP = IECore.V3f( s2["Ci"][i][0], s2["Ci"][i][1], s2["Ci"][i][2] )
+			transP = points["P"][i] * IECore.M44f.createTranslated( IECore.V3f(0,0,2) ) * IECore.M44f.createRotated( IECore.V3f(1,0,0) )
+			
+			self.failUnless( ( shaderP - transP ).length() < 1.e-5 )
+			
+		
+	
 	def tearDown( self ) :
 				
 		files = [
@@ -923,6 +958,8 @@ def tearDown( self ) :
 			"test/IECoreRI/shaders/sxTextureTest.sdl",
 			"test/IECoreRI/shaders/sxUniformPrimitiveVariableShaderParameterTest.sdl",
 			"test/IECoreRI/shaders/sxUniformPrimitiveVariableTest.sdl",
+			"test/IECoreRI/shaders/sxUserOptionTest.sdl",
+			"test/IECoreRI/shaders/sxCoordSystemTest.sdl",
 		]
 		
 		for f in files :
diff --git a/test/IECoreRI/shaders/sxCoordSystemTest.sl b/test/IECoreRI/shaders/sxCoordSystemTest.sl
new file mode 100644
index 0000000000..db8a424d27
--- /dev/null
+++ b/test/IECoreRI/shaders/sxCoordSystemTest.sl
@@ -0,0 +1,4 @@
+surface sxCoordSystemTest( string coordSysName = "current" )
+{
+	Ci = color( transform( coordSysName, "current", P ) );
+}