Modern manufacturing systems are often semi-automated, i.e. integrating both manual and automated operations. How, and even if, automation should be realized are often ad hoc decisions and not based on structured decision making. This paper examines three approaches to automation decisions: top-down, bottom-up, and contingency. Top management initiates a top-down approach to automation of production. On the contrary, when the decision about automation stems from e.g. the operators, a bottom-up approach is applied. We propose a third way, the contingency approach, which links decisions regarding automation to manufacturing strategies and competitive priorities of the company. Making automation decisions is one of several decision areas that emerge as a consequence of choosing a certain type of production system. The paper discusses important factors for the success of different approaches. Different approaches are illustrated with examples from Swedish manufacturing industry.