The best way I've found to do it is to have a need and ask for help in writing it. That's how I learned it. Also note, from Mark's addition of breaking down the _.pedit, it's a good idea to at least put the "." in always. There are some routines we've used here for a long time and when I loaded ADT4, they wouldn't work quite like they should. They made a layer in this fashion. (command "layer" blah blah blah). The routine worked fine, except the object wasn't on the right layer. In desktop, there is a new layer manager and it uses the command line layer, redefined to load its dialog form and its command structure. So, if I want to force the native layer structure, I have to add the dot.