All ties are influenced by pragmatic interests (benefits) and normative determinants. It is obvious that an individual accepts informal relationships when they serve his benefit or believes that he will receive some benefits in the future. And, of course, an individual tries to find other informal relationships when the current ones have disappointed him. The author examines informal relations in Korean society based on loyalty, reciprocity, hierarchy and aimed at obtaining resources bypassing formal procedures. Informal relationships based on group loyalty can develop on the basis of ties between relatives, friends, former colleagues or classmates, someone who was born and raised in the same district, village, who is part of the same clan or political group. There is a great influence of informal ties in South Korean business. It helps to enter or get a share of market, can reduce costs or commercial risk. Informal relations not only help to find partners and boost business, but are also a part of the solution to any problem. There are two key parameters of informal relationships: reliability and reciprocity. Lack of reciprocity results in weak tie. Reciprocity with lack of commitment reliability results in weak tie too. Direct client-patron relationships are stronger than ties with other co-members of a group or members of horizontal social networks. Informal group relationships can be defined through various contextual variables: reciprocity, ethical norms, collectivism, hierarchy, obligations to relatives, corruption.