This book reports the outcomes of a BELSPO (the Belgian Federal Science Policy Office) research project. The authors develop and estimate (parts of) a comprehensive model in which the micro-performance of SMEs is determined by a complex web of factors. These are situated at the level of the entrepreneur, organization and environment. In this modeling, a fit between individual, strategy, structure and environment is key to attain better performance in terms of, for example, efficiency or profitability. Strategy is assumed to be the linking pin between the entrepreneur’s (or his or her venture’s) strengths and weaknesses, and the opportunities and threats in the environment. In line with this contingency approach, the authors utilize a multi-disciplinary theoretical lens in combination with analysis techniques that allow for the identification of fits (and misfits), such as the analysis of conditional processes or dynamic multi-level QCA fit analysis.