Increasing demand for high degree of treatment as well as existence of highly resistant organics in wastewaters such as micropollutants has caused wider and ever increasing use of chemical treatment processes. In this paper developments in the chemical treatment as applied to mostly industrial wastewater in the last two decades are summarized and discussed. Two purely chemical means of treatment, chemical oxidation and chemical precipitation were considered and proven and widely used methods of treatment based on these principles were delineated. The review covers theoretical development, application areas and application bases. A brief evaluation of the state of development, advantages, drawbacks and need for further research was given for the processes reviewed.