Hi Clive, > When I call these functions during a debug session. must I have those modules > in the > same directory as the one I am debugging to get the debugger to step into > them or is there a directory search list for external script files which the > debugger will use? ZBS expects the project structure to be the same on both sides. The path leading to the project folder may be different (for example: /usr/me/myproject/a/b/c on the remote computer and d:\user\me-again\myproject\a\b\c on the local one), but inside the project folder it should be the same. Make sure that you either have the file opened or have editor.autoactivate set to true (http://studio.zerobrane.com/doc-faq.html#why_stepping_into_function_calls_doesnt_work_in_some_cases). If you enable "autoactivate", you will see a message in the output panel when the IDE fails to load/find the file the execution is stopped on the remote side. Is there any particular reason you have a different structure locally? Do you have a simple example you'd like me to check? Paul.