In this paper, we develop a comprehensive model of M&A success. We integrate fundamental constructs of different schools and discuss their interdependencies with M&A success. Our theoretical framework was tested empirically across a sample of 106 SME transactions in the machinery, electronic, and logistic industries in the German-speaking part of Central Europe. The results of our study support the demand for an integrative perspective and theory on M&A. M&A success is a function of strategic complementarity, cultural fit, and the degree of integration. Strategic complementarity also positively influences cultural fit and the degree of integration. Cultural fit positively influences M&A success, but surprisingly has a negative impact on the speed and degree of integration. The degree of integration is positively related to speed of integration. Copyright © 2013 John Wiley & Sons, Ltd.