Hi All , I've been trying to use a custom structure for describing the various edge properties of a graph. I'm defining a graph as the following struct edge_properties { int capacity ; double weight ; typedef struct edge_properties_tag kind ; // NOT SURE what this does ? }; typedef boost::adjacency_list<listS, vecS, bidirectionalS, property<vertex_name_t, std::string>, edge_properties > Graph; This allows me to create a Graph instance g. I've been trying to retrieve the edge properties via a get call, but have not been able to do so. To retrieve the vertex properties doing the following works property_map<Graph, vertex_name_t>::type v_names ; v_names = get(vertex_name,g) ; But on attempting to do something similar for retrieving the edge properties always fails with the following error message "test.cpp: 75: error: expected primary-expression before ',' token" test.cpp 71: property_map<Graph, edge_properties>::type epr; 72: property_map<Graph, vertex_name_t>::type v_names ; 74: v_names = get(vertex_name,g) ; 75: epr = get(edge_properties,g) ; I've tried various variants but seems to me i'm missing something fundamental in the way boost-graph keeps the edge_properties hidden. Any pointers will be useful. Thanks in advance