Operations and Maintenance (O&M) tends to be an under-supported area within the overall flood and coastal defence business. A fundamental review of this subject area was carried out within this study through a concerted action process in order to identify how best R&D might support the improved delivery of O&M benefits. Recommendations for future development of the area and a performance-based management framework for its delivery have been developed as part of this study. This framework fits into the strategic tiered approach to flood and erosion risk management, which Defra and the Environment Agency aim to develop in order to focus investment on the most beneficial areas for risk reduction. It should link with future Defra guidance on performance assessment for defences.