The post-acquisition integration phase is widely recognized as critical to the M&A process. However post-acquisition typologies suffer from inadequate empirical support or lack of comprehensiveness. This empirical paper responds to calls for methodological pluralism in M&A research, and uses a mixed method to assess the robustness of a leading post-acquisition integration typology. Through multiple cluster analyses, different post-acquisition strategies are identified and qualitative techniques allow them to be further explored. This approach overcomes some limitations of single method research in M&A and results in a more robust, fine-grained and extended post-acquisition typology. It enables a more nuanced perspective on the coexistence of exploration and exploitation gains with implications for practitioners and researchers.