This paper proposes a four-dimensional evaluation framework for software product family engineering. The four dimensions relate to the software engineering concerns of business, architecture, organisation, and process. The evaluation framework is intended for use within software developing organisations to determine the status of their own software product family engineering and the priorities for improving. The results of the evaluation can be used for benchmarking, roadmapping, and developing improvement plans. An initial evaluation of a real industrial case is presented to show the validity of the framework.