Last time I suggested FindBin in Re: accessing perl libraries, tye complained that FindBin is broken. However, ignoring that for a second, the above post would be my suggestion, and is, in fact, how I solve the same problem. Because my scripts and modules are all stored in a version control system, I want to ensure that the same extraction of the script and the same extraction of the libraries are working together - and I can have different levels running at the same time. So each one sets up the lib to its own relative path, and everything works perfectly.