In criminology, the role of guardianship in preventing crime has received significant international attention because of its focus on the function and importance of regular, informal citizens in controlling and preventing crime across contexts. Initially applied to property crimes, interest in its utility for understanding and preventing crime of an interpersonal nature (including child sexual abuse [CSA]) has increased in recent years. However, the personal nature of CSA highlights layers of complexity that require a more elaborate analysis of the mechanisms that underpin guardianship, especially in the home environment where most CSA occurs. The purpose of this discussion paper is to advance current understanding by applying Felson (1995) and Reynald’s (2010) conceptualizations of guardianship to the prevention of CSA in the home. Drawing on current literature, we apply a critical lens to examine factors that serve to promote or impede informal guardianship, and likelihood to intervene, within the home. From this analysis, we: (1) conclude that some (re)conceptualization of the dimensions of guardianship is required for understanding and preventing CSA in the home; (2) recommend proactive (parent and bystander education programs; place-based) and reactive (psychoeducation for parents whose children have been abused) prevention strategies; and (3) advocate for further theoretical and empirical investigation on this important issue.