A lot would depend on who would be changing the configuration. If only programmers, then putting it in a common module would make things easier; they would already know the syntax. If users were changing the configuration, then having a interface to validate their input would be best. Turning them loose with nothing but a text editor in your files is nothing but a recipe for disaster. But then you could have your interface rewrite the configuration files with something like Data::Dumper. Just remember that not using Perl modules for configuration means everyone has to learn yet another syntax.