This paper explores the role of rules, precedents, and procedures within the structural dimension of social capital. Rules are crucial to social structures and are often interconnected with roles and other aspects of group or institutional organisation. They play a vital role in shaping various aspects of social capital, including norms, trust, belonging, and shared understandings. Rules can be formal or informal, tangible yet often unspoken and tacit. They are instrumental in facilitating the functioning of social structures by establishing decision-making processes, resource mobilisation mechanisms, and guidelines for collective action. The existence of rules, alongside other structural elements, is essential for productive and sustained interactions among individuals. Unlike many other aspects of social capital, rules are more observable and reinforced through sanctions and incentives. However, their effectiveness ultimately depends on cognitive processes like mutual expectations and shared understandings. Rules are not only a manifestation of shared understandings but also significantly shape them. The nature of rule enforcement, monitoring, and sanctions has implications for solidarity, trust, and shared goals. How rules are perceived and interpreted by actors, particularly in terms of fairness, equity, and efficacy, carries significant meaning and influence in the lifeworld of individuals. Understanding the dynamics of rules within the structural dimension of social capital sheds light on their role in fostering social cohesion, trust, and collective action.