Software mass customization is a powerful business model as well as a powerful engineering model that enables software organizations to efficiently engineer customized variations of their software products. This document describes software mass customization in three parts. First is an overview of software mass customization and its benefits. Second is an introduction to a software engineering technology that enables organizations to quickly adopt software mass customization as part of their business and engineering models. Third is a collection of scenarios of how software product organizations can rapidly adopt software mass customization. 1.0 Software Mass Customization and its Benefits Software mass customization focuses on the means of efficiently producing and maintaining multiple similar software products, exploiting what they have in common and managing what varies among them. This is analogous to what is practiced in the automotive industry, where the focus is on creating a single production line, out of which many customized but similar variations of a car model are produced. The powerful,