Self-commitment is the willingness of individuals to commit to cooperation with a partner without the safety net of controls or sanction mechanisms. This article shows the unique performance contribution of self-commitment in the context of cooperative internationalization of SMEs in several ways: First, we use a multiparadigmatic approach to cooperation theory to argue why self-commitment as a coordination mechanism is particularly relevant in the context of cooperative internationalization. Second, we develop a new operationalization of self-commitment which takes the context of international cooperations into account. Third, we show empirically that self-commitment is particularly important in international cooperations by applying a PLS analysis to a sample of 146 Austrian, Czech, and Slovenian cooperating SMEs.