To build product populations, one must combine a top-down product line approach with a bottom-up reusable component approach. This leads to a largely independent development of components that must still be coordinated in the context of the products that will use them. Roadmapping of components and products, i.e. the planning of them in space and in time, is an important element of this coordination. We propose to create both product- and component-centric roadmaps that state mutual dependencies in terms of explicit versions and/or provided and required features. Such descriptions will ultimately lead to a time-dependent description of the architecture. The roadmaps can be specified in XML and published on the intranet, allowing tools to download the various individual roadmaps and check the consistency between them. The work as presented here is partially a formalization of existing practices, and partially a proposal for a new way of working.