The use of membranes in the water treatment industry is standardized practice, due to the requirement of filtration to take place in removing unwanted impurities from water. Membrane water treatment is done through the use of barriers that allow only specific substances to pass through the small pores of the membrane while not allowing other types of contaminants. There are a variety of membranes in use throughout the market which act as processes in treating groundwater, surface water, and wastewater to a level that is acceptable for industries and especially consumption. It is a rapidly growing industry, as a result of the need to combat low quality water sources such as rivers, lakes, wells, streams, and the ocean, in order to provide more alternative methods in supplying healthy, safe, steady, and accessible water to the masses. 

As per mentioned, there are different types of membranes which can be utilized for water treatment. The factors that necessitate which membrane would be more effective relies upon the types of contaminants existing in the water, and the desired water quality by the user. The two most common type of membranes used in the industry are: