Constructed wetlands have been increasingly used throughout the world for secondary and especially for tertiary treatment of wastewater and stormwater. If well designed and maintained, their effluents can meet the high standards required for reclaiming the water. One can also partially reclaim nutrients by harvesting the aquatic vegetation or by combining wastewater treatment with aquaculture. Constructed wetlands further provide certain ancillary benefits such as wildlife habitat function, recreational facilities etc. This paper gives an overview of treatment performances and consequent reuse possibilities, operation and maintenance requirements, costs and constraints interfering with the application of this technology.