Acquisitions and mergers of equals often fail to deliver shareholder value, largely because poor integration practices do not allow synergies to be created. The issue has been addressed by several studies from two different research streams: the first looks at the combination of resources after the acquisitions and the second focuses on the human factor. We propose an integrated model where the effects of these key aspects are tested simultaneously and where three independent variables are included: the extent of planning and knowledge from previous acquisitions and knowledge from previous relationships. We believe that through the model managers can prioritise their actions and select an appropriate time horizon for the integration.