Economic explanations of mergers and acquisitions tend to focus on issues of efficiency and strategic fit. When acquisitions fail, economic arguments tend to dominate the reasoning and explanations. While cohesive theory exists, empirical studies of acquisitions and divestitures of failed acquisitions based upon economic models are inconsistent and have poor explanatory power to identify clear success or failure factors. Non-economic explanations, on the other hand, generally lack an integration that goes much beyond suggesting that non-economic differences create integration problems and cannot explain why the economic synergies that organizations hope for often fail to materialize. In an attempt to address these challenges, we draw upon the stepfamily literature to propose several new concepts that provide insights into the factors that influence the success of acquisition execution and implementation. Since diversified corporations bear a striking resemblance to human stepfamilies, stepfamily theory can provide new managerial insights and prescriptions. Three main perspectives frame our view of merger and acquisition success: Biological Discrimination, Incomplete Institutionalization, and Deficit-Comparison. From these perspectives, we propose important factors and characteristics that can influence the ultimate success or failure of a merger or acquisition. From this metaphor, we provide managerial prescriptions for firms engaged in merger and acquisition activities to improve the probability for ultimate success.