I just installed boost 1.42.0 from macports using sudo port install boost. Everything worked fine. Now I have a project that I'm trying to build using a makefile. Everything builds fine until it comes to the file that needs the boost library. It says: src/graph.h:20:42: error: boost/graph/adjacency_list.hpp: No such file or directory That file is actually located in two places: /opt/local/include/boost/graph/adjacency_list.hpp and /opt/local/var/macports/software/boost/1.42.0_0/opt/local/include/boost/graph/adjacency_list.hpp In the file src/graph.h where it's looking for boost/graph/adjacency_list.hpp, the include statement is here: #include<boost/graph/adjacency_list.hpp> How do I make this work?