This site provides a description of the product line development method developed by the Software Engineering Institute (SEI). The graphic below depicts the Adoption Factory pattern discovered by the SEI. This pattern is the basis for the method described here. The patterns that constitute this larger pattern specify what needs to be done, and in some cases in which order, but not how to do it. The processes described in this site are a specific way of implementing the patterns. There are many others.

More complete information about the general method and specific methods that can be developed from it can be found in "Software Product Lines : Practices and Patterns" by Paul Clements and Linda Northrop, Addison-Wesley, 2001. ISBN: 0201703327