Abstract. Dynamic Aspect-Oriented Programming (d-AOP) is an important tool to implement adaptation in a wide variety of applications. In particular, large distributed infrastructures, middleware, and pervasive computing environments can greatly benefit from d-AOP to adapt software systems at run time. In this paper, we discuss the design of PROSE, an open source, generic platform for software adaptation. The paper discusses the join-points needed in practical systems together with examples of how they can be used, different implementation strategies and their practical implications. It also describes a highly efficient mechanism to implement stub and advice weaving.