Recent attempts to modernise irrigation tanks with a focus on physical rehabilitation, but little institutional development to maintain and manage them, have resulted in a vicious cycle. With the lack of maintenance and upkeep, rehabilitated tanks soon fall into disrepair, necessitating a new round of externally-induced rehabilitation. Yet, there are many tanks under traditional local management operating at a high level of performance equilibrium. A study of 41 tanks from 22 districts of eight Indian states was taken up under the IWMI-Tata Programme to identify the characteristics of high performing local- managed tank institutions. The lessons learnt from the study can form the basis for an effective institutional protocol that can enhance the effectiveness of tank rehabilitation and modernization