Woonerf is a Dutch word for an area, usually residential, where motorists and other users share the street without boundaries such as lanes and curbs. The term can be translated as "residential yard," reflecting its popularity in the Netherlands where private space is limited. In a woonerf, people on bikes and on foot have access to the whole street, not just sidewalks. Moreover, the street functions as a public living room, where adults gather and children play safely because vehicle speed is kept to a minimum.

Popularized in the Netherlands
Woonerfs were popularized in the Netherlands in the 1970's as a reaction to the growing dominance of the automobile over bicycles. During the first few years after World War II, Dutch transportation engineers began to emphasize relocating bicycles onto separate paths to accommodate the growing number of vehicles on the streets. This created a backlash, and the country soon moved in the opposite direction. Motorists were now forced to make accommodations for everyone else. The intent of this new approach was not to make cars disappear, but rather to integrate motorists and other users of the street into a shared space. The Dutch government developed traffic regulations for woonerfs in 1976, though the first woonerf was built in the city of Delft a decade earlier [1]. Since then a variation on the woonerf designed for commercial districts, known as the "winkelerf," has come into use as well.