Fish is a critical contributor to global food and nutrition security and demand for it is projected to continue to rise. Despite the growth of aquaculture, capture fisheries will continue to supply most of the fish consumed in much of the developing world in the coming decades. The great majority of these fisheries are small-scale, operating in rivers, lakes and wetlands and coastal seas. Sustaining and increasing the contribution of SSF to poverty reduction and food and nutrition security requires addressing interrelated problems. Pressures from within and external to SSF threaten the sustainability and equitable distribution of SSF benefits. The complexity of SSF, both in their ecology and the social and institutional environments they operate in, has thwarted the search for universal solutions. Compounding this, SSF are frequently accounted for poorly (or not at all) by fisheries, development and environment policy. This oversight is attributable, in part, to limited understanding of the scale and reach of benefits of SSF and low visibility of the very many people whose livelihoods, nutrition and health depend on SSF. Whilst donors and organisations have sought to seek solutions, their efforts to date have been piecemeal, unaligned or even misaligned.