1. Introduction
Runtime adaptation of software systems has received considerable attention in research areas such as software architecture, product line engineering, or self-adaptive systems. The need for runtime adaptation of systems is obvious for new development paradigms such as mobile and pervasive computing or service-oriented systems to deal with context changes. How-ever, even in more traditional environments practitioners are demanding capabilities to adapt a system to changing conditions during system operation. For instance, Enterprise Resource Planning (ERP) software is inherently complex and feature-rich. Runtime adaptation allows providing just the right set of features required to support particular business processes.