Component based and model based development (CBD vs. MBD), in their various interpretations, are in focus in many efforts in order to better handle the efficient development of increasingly complex embedded systems. We elaborate on what CBD and MBD represent, on their differences and similarities. Although CBD represents a bottom-up approach whereas MBD is more top-down in nature, it turns out that the concepts have much in common and can benefit from cross-fertilization. In particular, MBD requires improved handling of ?model? components, and CBD requires improved component models to assure component composition and reuse. We discuss their mutual opportunities and other relationships.