Modern distributed object systems pass remote parameters based on their runtime type. This design choice limits the expressiveness, readability, and maintainability of distributed applications. While a rich body of research is concerned with middleware extensibility, modern distributed object systems do not offer programming facilities to extend their remote parameter passing semantics. Thus, extending these semantics requires understanding and modifying the underlying middleware implementation. This thesis addresses these design shortcomings by presenting (i) a declarative and extensible approach to remote parameter passing that decouples parameter passing from parameter types, and (ii) a plugin-based framework, DeXteR, that enables the programmer to extend the native set of remote parameter passing semantics, without having to understand or modify the underlying middleware implementation. DeXteR treats remote parameter passing as a distributed cross-cutting concern. It uses generative and aspect-oriented techniques, enabling the implementation of different parameter passing semantics as reusable application-level plugins that work with application, system, and third-party library classes. The flexibility and expressiveness of the framework is validated by implementing several non-trivial parameter passing semantics as DeXteR plugins. The material presented in this thesis has been accepted for publication at the ACM/USENIX Middleware 2008 conference. / Master of Science