Next year at OOP 2007 Frank and I will offer a session about MDA and product line engineering . In this session we'll show how to use MDA with product line techniques in a pragmatic way by using Open Source Java products. We'll underline the importance of Business Rules , so that we will be able to build a flexible solution for some domains which is based on the same business requirements . This should be a practical session and not a theoretical one as often the case in product line sessions. I would also like to thank Gernot who made this session possible!