Imported a Maven project, where some modules depend on others, e.g. services module depends on api module. The project build successfully from within IDEA. (Using the clean lifecycle followed by the package lifecycle, initiated from Maven Build panel.) However, in the editor, if I view a class in the services module, classes defined in the "api" module are not resolved. So, I go to the module dependencies and add the dependencies there. This picture has a similar dependency: http://www.jetbrains.net/jira/secure/attachment/23319/3-verified-module-dependency.jpg (note the webapp-reference-core has been added as a dependency). In my case, I add the api module as a dependency in the services module. I save the dialogs, and indeed all errors disappear in the editor. However, when I exit IDEA and start it again, the inter-module dependencies are lost. The services module no longer depends on the api module. This inhibits navigation between files, which I rate as a High severity level. This may be the same/similar issue as http://www.jetbrains.net/jira/browse/IDEADEV-22555