The family business, the bedrock of the national and global economy, is fertile ground for scientific research. In this book, we enrich the literature by highlighting a crucial aspect: governance. Our study focuses on the influence of the family on the governance of unlisted Moroccan family businesses across generations. Adopting a multidisciplinary theoretical approach, we combine contractual and relational perspectives on corporate governance. The research is structured around an exploratory study via semi-structured interviews with 17 family managers, followed by two longitudinal studies. Our findings reveal that family managers, whether founders or successors, wield predominant power, rarely counterbalanced by controlling bodies, thus shaping the governance structure of companies. Moreover, family influence on governance varies according to the context of each company and family, and depends mainly on family cohesion.