The development of dependable embedded automotive systems faces many challenges arising from increasing complexity, coexistence of critical and non-critical applications, and the emergence of new architectural paradigms on the one hand, to short time-to-market intervals on the other hand. This situation requires tools to improve efficiency and consistence of development models along the entire development lifecycle. The existing solutions to date are still all too frequently insufficient when transforming system models with higher levels of abstraction to more concrete engineering models (such as software engineering models). Future automotive systems require appropriate structuring and abstraction in terms of modulariza-tion, separation of concerns, and supporting interactions between system, and component development. However, refinement of system designs into hardware and software implementations is still a tedious task. The aim of this work is to enhance an automotive model-driven system engineering framework with software-architecture design capabilities and a model-transformation framework to enable a seamless description of safety-critical systems, from requirements at the system level down to software component implementation in a bidirectional manner.