A sento is a Japanese communal bath house. Typically these bath houses are quite utilitarian, with one large room separating the sexes by a tall barrier, a line of showers along one wall and a single large bath for the already washed bathers to sit in along the other. Since the 1980s these communal bath houses have been decreasing in numbers as more and more Japanese bath at home, and some Japanese are concerned that without the skinship of mutual nakedness, children will not be properly socialized.

In an effort to differentiate themselves from the home bath, many sentos now offer benefits such as mineral baths, massages, cafeterias and water slides, but community baths are still increasingly scarce in urban Japan.