This paper describes and analyses the system of traditional fishing rights in Pulicat Lake, the second largest lagoon of India spreading across the States of Tamil Nadu and Andhra Pradesh. The system entails the granting of entitlements to eligible members of a particular community for undertaking specified fishing activities on certain designated fishing grounds of the lake. Whereas the system enjoys legitimacy with the lagoon fishermen and contributes to the prevention of conflicts within this group, it has come under increasing pressure from outsiders, including marine fishermen and dispossessed peasants and tribals. The paper suggests the need for strengthening the system through formal legalization and by the incorporation of control measures over fishing capacity and fishing intensity.