Despite the trend in investigating combinations of MC practices that form packages or systems, there is ambiguity about what is meant by a "control package" or "control system". In this paper, we address questions related to MC as a package and as a system, both from a conceptual and empirical perspective. The purpose of our study is to clarify a number of issues, so as to guide future research in this area. We do not claim to have all the answers. Rather we make a number of assumptions explicit to show when it is important to address multiple MC practices simultaneously, why this is the case, and what the empirical implications are. Our research directly relates to the systems approach to contingency theory and the literature’s struggle to clearly define its most fundamental concept, i.e., "internal consistency". Our analysis provides a formal definition of "internal consistency" and shows how it can be used to conceptualize MC systems, thereby giving contingency theorists the necessary ingredient to move forward.