Related products frequently share much of the same software, with only a few differences realizing product-specific functionality. However, much of the challenge of developing related products comes from managing these differences.

When faced with this challenge, organisations often turn to their Configuration Management (CM) system to manage the variability between products. We will illustrate this using case studies, and then discuss the reasons why this approach is rarely wholly successful.

We will then consider another case study, of an organisation that recognized that use of CM alone was insufficient to manage variability. This organisation has adopted a Variant Management approach, which addresses the problems of a pure CM approach, by enabling the development of a group of related products as a whole, rather than as individual, independent projects. CM still plays an essential role in this organisation but this role has changed with the introduction of Variant Management.

Keywords: variant management, configuration management, software product lines, software families, software reuse, software process improvement

I presented this at the 3rd BCS CMSG conference last week.