There are basically two forms of aquaculture. One produces food (shrimp, salmon) mainly aimed for (export) markets of industrial high-income markets. People in one place on the planet demand a commodity produced in another place without perception of possible site-effects, like mangrove destruction caused by shrimp farming. A major driver is international demand and trade opportunities for commodities as well as governmental policies supporting the development. The other produces food mainly for local/national consumption. Such aquaculture is not capital intensive and often complements other sources of food.

For each of the following groups there would be an assessment of environmental (what we are gaining and at what short and long term costs) and social/economic side effects of current practices. There would be syntheses of the impacts of direct discharges of wastes into aquatic systems, the impacts of escapes, impacts of chemicals and antibiotics used in aquaculture, the losses of ecological services of mangroves and other ecological systems due to aquacultural practices, comparisons of impacts of fish food that comes from higher versus lower tropical levels. The essence of these discussions would be an attempt at a more complete socioeconomic analysis that takes into account environmental and social externalities and that emphasizes the necessity of proper institutional frameworks for aquaculture: salmon; shrimp, catfish, trout, milkfish, molluscs.

The road to sustainability will need to include: the importance of full costing and proper institutions; economic and social incentive structures that promote sustainability; the lessons from agriculture; policy recommendations. These are lessons of combined social-ecological impacts on agriculture/aquaculture from which basic principles for sustainable aquaculture could be derived.