For software-intensive products like car electronics the trend is to offer more and more product variants. Increasing market demands and pressure from competitors force enterprises to diversify their product range leading to growing complexity. Product families tackle this problem by reusing existing software and hardware artefacts. The development process is structured into domain engineering ('development for reuse') and application engineering ('development with reuse'). However, deriving products in application engineering still lacks methodological support. This book provides the ConIPF (Configuration in Industrial Product Families) Methodology. It is one of the first attempts to support product derivation during application engineering with a combination of product line engineering and knowledge-based configuration.