In the simplest terms, I'm trying to create a program that I can add to ENVI's menu structure that will call the ROI Tool which exists at Basic Tools-> Region of Interest-> ROI Tool. When I go to the envi.men file, I can see that that menu option corresponds to the following code (in envi.men): {ROI Tool} {roi tool} {envi_menu_event} I have this basic, bare bones .pro that I want to accomplish the same thing as that menu selection: pro callROI, event xmanager, envi_menu_event, base, EVENT_HANDLER='roi tool' end I know that, at the very least, the ID, 'base', is wrong but I can't seem to figure out what that should be. Also, my other arguments may be out of order and/or wrong. I would greatly appreciate some help in calling this ENVI function/operation of opening the ROI Tool.