This document is the third of the ten policy papers to be prepared under the IMPSA Program. It is a synthesis of two Staff Working Papers on the issues related to this topic, i.e., strategies for operation and maintenance (O&M) and rehabilitation and modernization (R&M). The purpose of this paper is to propose a set of guiding principles and feasible strategies for O&M and R&M of irrigation systems in Sri Lanka, which would contribute to achieving high performance in these systems in the future. The paper also sets out broad guidelines for the implementation of the strategies proposed.