Title: Co-operative, prevent or complement? - An essay on the relationships between control systems.  Authors: Kim Eriksson and Victoria Karlsson Purpose: The essay aims to describe the relations between control systems and how they related to each other, based on an operationalization of the control systems.  Research question: What are the control systems relations to each other? With regards whether control systems co-operative, prevents and/or complement each other. Theoretical framework: The essays theoretical framework is based on Malmi and Browns (2008) description of five different control systems and control mechanisms associated with each control system.    Research methodology: The method was based on three different data collection methods. These methods were observations, documentation, and semi-structured interviews. Conclusions: It is concluded that the control systems has comprehensive relations. Control systems have more, than one, relation to each other.