The paper introduces a concept of structural cohesion based on network node connectivity, defining it as the minimum number of actors whose removal would disconnect a group. This concept is linked to social embeddedness through hierarchical nesting of cohesive structures. The authors demonstrate its empirical applicability in two different settings: adolescent friendships and political activity of large businesses. They argue that structural cohesion is a key dimension of social solidarity, distinct from other measures like density or distance. The paper also discusses the theoretical implications of structural cohesion for various fields, including sociology, political science, and social epidemiology. The authors propose a method for identifying structurally cohesive groups, called cohesive blocking, which reveals nested structures within networks. They show that structural cohesion is related to social embeddedness, with deeper nesting indicating greater embeddedness. The paper also addresses alternative approaches to structural cohesion, highlighting the advantages of the proposed method. The authors use empirical examples to demonstrate the relevance of structural cohesion in understanding social phenomena, showing that it can add value to empirical research in different settings. The paper concludes that structural cohesion provides a new way to understand social groups and their relationships, with implications for various fields of study.The paper introduces a concept of structural cohesion based on network node connectivity, defining it as the minimum number of actors whose removal would disconnect a group. This concept is linked to social embeddedness through hierarchical nesting of cohesive structures. The authors demonstrate its empirical applicability in two different settings: adolescent friendships and political activity of large businesses. They argue that structural cohesion is a key dimension of social solidarity, distinct from other measures like density or distance. The paper also discusses the theoretical implications of structural cohesion for various fields, including sociology, political science, and social epidemiology. The authors propose a method for identifying structurally cohesive groups, called cohesive blocking, which reveals nested structures within networks. They show that structural cohesion is related to social embeddedness, with deeper nesting indicating greater embeddedness. The paper also addresses alternative approaches to structural cohesion, highlighting the advantages of the proposed method. The authors use empirical examples to demonstrate the relevance of structural cohesion in understanding social phenomena, showing that it can add value to empirical research in different settings. The paper concludes that structural cohesion provides a new way to understand social groups and their relationships, with implications for various fields of study.