Variability management has long been recognized as a key part of software product family development. This article builds on this notion by presenting a set of Web service related technologies in the context of variability management. Additionally we adapt an existing process for planning variability for use with our technologies. We expect that Web service technology, already very successful in the domain of enterprise applications, would emerge as the integration technology of choice for constructing so called product family populations, i. e. populations of products constructed from multiple, independently developed product families