Membrane filtration systems have been focusing and increasing rapidly in the filed of drinking water treatment because of several reasons. We describe briefly the present state of membrane filtration processes for drinking water treatment in Japan: including background, objectives, membrane suppliers, and some cases of actual plants.

• Kiso Yoshiaki(Dept. Ec이ogical Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi 441-8580, Japan) Corresponding author