Hi, I trying to wrap my head about the usage of iterator_property_map<RandomAccessIterator, OffsetMap, T, R> What I am trying to do is the following: create a map like color with key a graph_node and value type of a struct like struct foo { int numbervists; int color; } so I can use that in a breadth first like algorithm. The example shows me how to do it for an int but do not know how to change typedef boost::graph_traits<Graph>::edge_descriptor Edge; typedef boost::property_map<Graph, boost::id_tag>::type EdgeID_PMap; EdgeID_PMap edge_id = get(boost::edge_index(), G); boost::iterator_property_map<int*, EdgeID_PMap, int, int&> capacity_pa(capacity, edge_id), flow_pa(flow, edge_id); to use foo instead of int. In my understanding, I would have to change int* to a RandomAccessIterator to to Iterator that has foo as value type. But I am kind of lost how to construct such a thing. Arne