this book constitutes the thoroughly refereed post-proceedings of the international workshop on software architectures for product families iw-sapf-3, held in las palmas de gran canaria, spain in march 2000. the 24 revised full papers presented together with an introduction and two surveys were carefully reviewed and selected for inclusion in the book. the papers are organized in topical sections on product family practice, business, product family concepts, product family methods, evolution, and product family techniques.