Earlier research on mergers and acquisitions presents emotions as something problematic and negative that must be neutralized or controlled. However, emotions can also be the reason why individuals or organizations thrive. Thus, this study sets out to determine how employee emotions influence post-acquisition integration, paying particular attention to positivity in emotions. Taking a slightly unorthodox stance, this study adopts an abductive research structure guided by a moderate constructionist research philosophy in order to build a theory that is closely connected to empirical evidence. The empirical evidence that is crucial to abduction arises from an in vivo case study in two different acquisitions, where data collection centers on qualitative interviews and employee surveys. 

Emotions in general arise through appraisal—an evaluation of how pleasing or displeasing a triggering event is considered. Both individuals and groups can experience them. At work, emotions are triggered by work-related events and can influence work-related behavior. According to the findings of this study, a key positivity trigger at work is interactive communication. Previous research has indeed confirmed that communication is a key aspect during integration because social interaction and employee engagement can create a feeling of belongingness to the new organization. However, emotions are dynamic and vary within and between individuals and groups. According to the findings of this study, a key reason for this evolving nature of emotions is the surrounding emotional climate. An emotional climate refers to a socially constructed working atmosphere. It is visible in the predominant collective emotional states that arise through social interaction between organizational members. A positive emotional climate can improve organizational identification and performance, and thereby facilitate organizational change. 

The key theoretical contribution of this study is threefold. First, it acknowledges positive emotions. This can help overcome the previous negative bias in the emotion-centric acquisition literature. Second, it considers emotions in a more balanced manner, not as isolated instances but as both individual and collective instances, paying special attention to the relevant emotion triggers. This sheds more light on how and why emotions emerge during change periods, increasing the level of theorization in the field. Third, this study offers a more dynamic view of emotions in an organizational context, also shedding light on how to manage collective emotions following acquisitions. Together, these findings help answer the fundamental question of how to make acquisitions more successful. 

For practitioners, the key contribution is in the analytical power of the suggested framework. Managerially, the key elements for creating positive post-acquisition change are the chosen integration strategy and the managerial skills necessary to create the desired positivity. With regard to employee emotions, acknowledging the different levels of emotions and their triggers can help emphasize positivity and alleviate negativity. Simultaneously, an emphasis on the post-acquisition organization can help overcome us versus them thinking. With regard to communication, information sharing is essential to ensure day-to-day functions, but interaction is crucial for long-term engagement and motivation. With regard to the emotional climate surrounding change, awareness of the pre-acquisition climate and possible sub-climates can help predict fluctuations.