Underlying the 1995 UN Straddling Stocks Agreement was the central notion that straddling and highly migratory fish stocks could best be managed through regional (particularly newly formed) institutions. This article explores a number of the constraints and possibilities for the development of institutions on a wider scale. Amongst these are the problems associated with transforming FAO Article VI institutions into executive management organisations. Secondly, multi-party regional agreements require a mutually acceptable distribution of benefits and costs. Matching those elements can be lengthy and complex, especially in those instances in which external parties are the principal benefactors and weak coastal states have no direct distant water fishing interest or capability. New institutions, for this reason, have tended to be responsible for single species such as tuna. There is some risk accordingly that straddling fish stocks may receive less institutional attention. Other important issues centre on the role of non-parties, and disputes between organisations over competence to manage species.