Building on the codification and dynamic capabilities literatures, we pursue deeper insight into the underlying mechanisms of deliberate learning in the context of postacquisition integration. We argue that experience codification gives rise to inertial forces that hamper the customization of routines to any given acquisition. We theorize, therefore, that successful acquirers develop higher-order routines-as manifested in two complementary sets of concrete organizational practices-that prevent the generalization of inapplicable ('zero-order') codified routines. After drawing on in-depth qualitative data to help build our theoretical argument, we test it formally with unique survey data on 85 active acquirers.