Product certification and ecolabelling are tools that can be used to support fisheries management. These tools, while interrelated and serving the same goal, have important differences as currently applied in fisheries. Product certification is commonly a measure mandated by governments, often mutually agreed upon by regional fisheries management organizations, in order to ensure that only legally harvested and reported fish landings can be traded and sold in the domestic or international markets. This technical paper provides information on important institutional features and characteristics of product certification schemes. The principal objective of an ecolabelling scheme is to create a market-based incentive for better management of fisheries by creating consumer demand for seafood products from well-managed stocks. This paper provides information on the theoretical foundation, institutional arrangements and relationship with international trade law of ecolabelling programmes for fish and fishery products. It also discusses trade access concerns with ecolabelling programmes and examines their operational features.