In developing countries, the wise use of natural and artificial wetlands for water purification is particularly valuable and exploitable for the protection of water quality in catchments, rivers and lakes. Constructed wetlands are potentially good, low-cost, appropriate technological treatment systems for domestic wastewater in rural areas. Better still, they can be integrated into agricultural and fish production systems where the products are useable and/or re-cycled for optimal efficiency. However, currently, constructed wetlands are rarely installed. The reasons for this are discussed drawing attention to the limitations of aid programmes from donor countries and the need for in-house research, training and development. Recommendations for the development and wider use of constructed wetlands in developing countries are made.