River and wetland restoration has emerged as a worldwide phenomenon and is becoming a highly profitable business. Although researchers worldwide know a lot about restoration practices in Europe and the United States, we have only scant information about the activities in Japan, where more than 23,000 river restoration projects have been conducted during the past 15 years. In Japan, restoration is a daunting business because of the high human population density, urbanization, and harsh environmental conditions. Here we provide an overview of the various restoration activities in Japan and discuss the lessons that we can draw from them.