Abstract: Systematic testing of object-oriented software turned out to be much more complex than testing conventional software. Especially the highly incremental and iterative development cycle demands both many more changes and partially implemented resp. re-implemented classes. Much more integration and regression testing has to be done to reach stable stages during the development. In this presentation we propose a diagram capturing all possible dependencies/interactions in an object-oriented program. Then we give algorithms and coverage criteria to identify integration resp. regression test strategys and all test cases to be executed after some implementation resp. modification activities. Finally, we summarize some practical experiences and heuristics.