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Communication middleware simplifies the construction of component-based distributed applications. However, the lack of flexibility in the construction of the middleware itself imposes limitations and is a major concern. While applications can detect changes in their execution environment, they cannot customize the underlying middleware to better accommodate these changes. To solve this problem, recent research in reflective middleware uses techniques derived from previous work in computational reflection to add flexibility to middleware. Reflective middleware exploits the concept of the meta-object protocol introduced by Kickzales. The approach combines the ideas of computational reflection and object-orientation. His model distinguishes between base level and meta-level objects. The base level concerns the functional aspects of a system while the meta-level concerns aspects that include policies, mechanisms, or strategies. The base level of a reflective middleware addresses the functionality of the application program while the meta-level designates collections of components that form the internal architecture of the middleware platform. Reflection can inspect and modify these components and change the behavior of the middleware.