The VITAL-KR provides the basic sub-structure for integrating a number of representation and inference paradigms as a means towards experimenting in the design of hybrid systems. In this paper we give an overview of the VITAL-KR, in particular illustrating how it supports the development of hybrid applications, as well as the integration of new inference systems. We believe that the VITAL-KR provides a number of advantages over alternative hybrid AI programming environments. Its communication primitives are generic, as they do not depend on the structure of a particular knowledge representation system; it is extendible, as it provides well-defined mechanisms for integrating new inference systems; it enjoys a formal, unambigous specification; and it comprises mechanisms to ensure the consistency of the overall, hybrid KB.