Right I've got past my vc8 sp1 problems (at some point it had uninstalled some dll it needed) and I now have a working BGL. I did want to compile in the IETL sparse spectrum code but when I do I get the following errors. Perhaps you can help? Using boost build at: C:\Dev\ThirdParty\boost\RC_1_34_0\boost/tools/build/v2 Using boost at: C:\Dev\ThirdParty\boost\RC_1_34_0\boost Using python at C:\apps\Python25 Using IETL at C:\Dev\ThirdParty\C\ietl-2.2 Building Boost.Regex with the optional Unicode/ICU support disabled. Please refer to the Boost.Regex documentation for more information (and if you don't know what ICU is then you probably don't need it). ...patience... ...patience... ...found 4205 targets... ...updating 5 targets... compile-c-c++ bin.v2\msvc\release\threading-multi\sparse_spectrum.obj sparse_spectrum.cpp C:\Dev\ThirdParty\boost\RC_1_34_0\boost\boost/python/docstring_options.hpp(65) : warning C4099: 'boost::python::objects::function' : type name first seen using 'struct' now seen using 'class' C:\Dev\ThirdParty\boost\RC_1_34_0\boost\boost/python/object/function.hpp(17) : see declaration of 'boost::python::objects::function' C:\Dev\ThirdParty\boost\RC_1_34_0\boost\boost/python/numeric.hpp(98) : warning C4099: 'boost::python::numeric::array' : type name first seen using 'struct' now seen using 'class' C:\Dev\ThirdParty\boost\RC_1_34_0\boost\boost/python/numeric.hpp(20) : see declaration of 'boost::python::numeric::array' C:\Dev\ThirdParty\boost\RC_1_34_0\boost\boost/iterator/transform_iterator.hpp(91) : error C2872: 'detail' : ambiguous symbol could be 'boost::detail' or 'boost::numeric::ublas::detail' .\boost/graph/sparse_spectrum.hpp(100) : see reference to class template instantiation 'boost::transform_iterator<UnaryFunction,Iterator>' being compiled with [ UnaryFunction=boost::graph::python::basic_descriptor<void *,boost::undirectedS>::create, Iterator=boost::adjacency_iterator<boost::adjacency_list<boost::listS,boost::listS,boost::undirectedS,boost::property<boost::vertex_index_t,size_t>,boost::property<boost::edge_index_t,size_t>>,void *,boost::detail::out_edge_iter<std::list<boost::detail::sei_<void *,std::list<boost::list_edge<void *,boost::property<boost::edge_index_t,size_t>>>::_Iterator<true>,boost::property<boost::edge_index_t,size_t>>>::_Iterator<true>,void *,boost::detail::edge_desc_impl<boost::undirected_tag,void *>,__w64 int>,int> ] src\sparse_spectrum.cpp(31) : see reference to function template instantiation 'void boost::sparse_spectrum<Graph,std::vector<_Ty>,std::vector<double>>(Graph &,int,int,EigenvectorMatrix &,EVector &,double,double)' being compiled with [ Graph=boost::graph::python::Graph, _Ty=Vector, EigenvectorMatrix=std::vector<Vector>, EVector=std::vector<double> ] src\sparse_spectrum.cpp(59) : see reference to function template instantiation 'boost::python::tuple boost::graph::python::sparse_spectrum<boost::graph::python::Graph>(Graph &,int,int,double,double)' being compiled with [ Graph=boost::graph::python::Graph ] C:\Dev\ThirdParty\boost\RC_1_34_0\boost\boost/iterator/iterator_adaptor.hpp(263) : error C2872: 'detail' : ambiguous symbol could be 'boost::detail' or 'boost::numeric::ublas::detail' ... let me know if you need the rest of the output. Thanks, John.