This paper, based on fieldwork conducted in Singapore and Malaysia, examines the social foundations and organizational principles of Chinese business firms focussing in particular on the inclination to incorporate personal relationships in decision making. It identifies three key aspects of personalism: personal control, personal guanxi relationships, and interpersonal trust or xinyong. Personal control is effected largely through depending on people whom one personally trust as this would reduce risks and afford better business control. The paper also examines the dynamics between guanxi and xinyong and how these ideals are played out in reality. A central argument is that economic decisions are not based solely on market considerations. Rather, they are embedded int he context of larger social relations and institutional forces which shape, reinforce, as well as challenge, a set of behaviours or organizational structures.