This study is to investigate how acquiring firms within the Swedish construction industry work towards successful post-acquisition integration during the early stages of post-acquisition and which factors they consider when doing so. When researching the five cases, the study adopted a qualitative approach, using semi-structured interviews with five managers from acquiring firms to gather in-depth, first-hand data for thematic analysis. The empirical findings highlight the significance of corporate culture, organizational structure, and leadership structure in the integration process. Acquiring firms prioritize cultural compatibility, recognizing that differences can hinder successful integration. They also emphasize the positive impact of similar business models and the creation of new leadership groups combining resources and capabilities. Supportive leadership plays a crucial role in smoothening the integration process. To achieve a successful post-acquisition integration, firms in the Swedish construction industry focus on assessing corporate culture compatibility, restructuring leadership, and effective integration planning. They aim to integrate cultures, develop thorough integration plans, and ensure employee satisfaction and financial success. The studied cases challenges theories that emphasize organizational structure as the main obstacle in acquisitions, suggesting that cultural factors are more critical. Similarly, it contradicts theories highlighting directive leadership, emphasizing the importance of supportive leadership instead. The study contributes to the understanding of integrating human resources, cultural factors, and clear integration plans as essential elements for acquisition success.