destynova wrote: Yes, but they don't provide the source code. Not for the windows DLLs... but for a lot of open source libraries, you do get the source code. Heck, even for MFC you get the source (even if it might be cryptic). Again, comparing yourself to a large company is really not a fair comparison at all, specially to a customer who paid for development. In any case, as a project manager (and engineer/developer), I could tell you that wouldn't fly in my company. Having a contractor say he used his own library and can't provide the code for certain sections would be unacceptable.