In this paper, we present a proposal for a UML profile called `Embedded UML'. Embedded UML represents a synthesis of various ideas in the real-time UML community, and concepts drawn from the Hardware-Software co-design field. Embedded UML first selects from among the competing real-time UML proposals, the set of ideas which best allow specification and analysis of mixed HW-SW systems. It then adds the necessary concept of underlying deployment architecture that UML currently lacks in complete form, using the notion of an embedded HW-SW `platform'. It supplements this with the concept of a `mapping', which is a platform-dependent refinement mechanism that allows efficient generation of an optimised implementation of the executable specification in both HW and SW. Finally, it provides an approach which supports the development of automated analysis, simulation, synthesis and code generation tool capabilities which can be provided for design usage even while the embedded U...