Business processes contain value-added and abuse prevention activities. Most modelling techniques do not provide a rationale for abuse prevention activities. Such a rationale is needed when redesigning business processes. In this paper we propose to consider business processes as the main regulatory mechanism that an organization uses to survive and flourish in its environment. We propose a theoretical framework based on the concept of Homeostasis, the maintenance of identity in a changing world. The framework classifies business processes into three levels and explains the interconnections between processes at different levels and the organization’s environment. Based on this framework, we extend the “Use and Misuse Cases” technique to support modelling of value-added and abuse prevention activities and their interconnections with the organization’s environment. We thus provide the needed rationale for business process redesign.