This chapter examines the theories used in the literature on risk in family businesses. Agency Theory is the dominant framework for analyzing conflicts between ownership and control, information risks, and opportunistic practices in family-controlled companies. Behavioral Agency Theory and Socioemotional Wealth Theory, by contrast, explore the affective and identity dimensions that shape risk perception, explaining why families tend to be averse to decisions that threaten continuity or reputation. Stewardship Theory proposes a fiduciary view of family governance, in which strategic caution reflects intergenerational values and moral commitment. The Resource-Based View (RBV) and the related notion of familiness shift the focus to the idiosyncratic bundle of tangible and intangible resources that condition both risk-taking and the capacity to absorb shocks in family firms. Finally, Legitimacy Theory clarifies how risk decisions are influenced by the need to preserve social approval and a “license to operate” within institutional and community contexts, particularly through disclosure, governance, and corporate social responsibility choices. This chapter examines how the main theories have been applied to investigate various aspects of risk in family businesses, which will be explored in the subsequent chapters.