While these are all interesting modules, they all look pretty complex, and from what I can tell they read and parse the files themselves. At least the Module::Dependency suite and the Module::Info suite do, i cant figure out how the Devel::ModInfo suite works other than it has alot of XML and sounds frightenlingly like JavaDocs. Parsing can get quite hairy, i can already see where code in Module::Dependency had to branch for cases of "use base". My script (which is really just a quick one off, not a full system like these) uses the symbol table, which tends to be a much more reliable means of tracking inheritance and methods, since you are pretty much assured that if its in the symbol table, its there.