Product family engineering is one form of strategic re-use that can be particularly effective. However, establishing a product family is not a simple matter. Technical and non-technical aspects have to be dealt with to reap the benefits of organization-wide software reuse. Especially if the scope surpasses that of a single product domain, this can be challenging. The family may then span several product groups, each of which might have its own product family installed. Product variability and the number of people involved will be larger, calling for appropriate measures. We present a strategy for software reuse in complex, software-intensive medical systems. We describe its implementation in a platform architecture, an organization and its processes, as well as its evolution in response to strategic changes. The case presented here is especially interesting because it deals with a hierarchical product family for a wide range of complex systems, in a large organization.