In this paper, we present a model, a strategy and a methodology for planning integration and regression testing from an OO model. We show how to produce a model of structural system test dependencies which evolves with the refinement process of the OO design. The model, that is the test dependency graph, serves as a basis for ordering classes and methods to be tested for regression and integration purposes (minimization of test stubs. The mapping from UML to the defined model is detailed as well as the test methodology. While the complexity of optimal stub minimization is exponential with the size of the model, an algorithm which computes a strategy for integration testing with a quadratic complexity is detailed This algorithm provides an efficient testing order for minimizing the number of stubs. A comparison is given of various integration strategies with the proposed optimized algorithm (a real-world case study illustrates this comparison). The results of the experiments seem to give nearly optimal stubs with a low cost despite the exponential complexity of getting optimal stubs.