Hi, Maybe this will help Normally if one has a module, lets call it mymodule then one would provide theming functions along the lines of function theme_module_page(...) { } function theme_module_paragraph(...) { } Then when calling these functions one would use theme('module_page', ...); and theme('module_paragraph', ...); The theme function is the key here, it not only provides the override mechanism but also only makes a function call if it finds an valid theme function. So there is no need for the caller to do any checking. Then in using phptemplates one can override with either function phptemplate_module_page(...) { } or function themename_module_page(...) { } (I think there are similiar ways using the other template engines) Nevets