This article presents one case study of public participation in urban planning: the "Face Your World" project that took place in 2005 in the suburban area of Slotervaart, close to the Dutch city of Amsterdam. "Face Your World" was a participation project that aimed at engaging both younger and immigrant inhabitants of Slotervaart in the urban renewal of their neighborhood. The goal was to design a new neighborhood park that would be supported by the different ethnic groups in Slotervaart. Dutch artist Jeanne van Heeswijk initiated this public participation and design project. The core of the project was a computer game/design tool called the Interactor. The participants worked between January and July 2005 on the design of this park and on March 1, 2006, the city council of Amsterdam approved the design. If all goes as planned, the park will be realized by 2010. This analysis of the case study is based on 28 in-depth interviews with different stakeholders involved in this participation process. The article asks in what form and under which circumstances public participation in urban planning can be an effective means in the process of seeking the acceptance of urban interventions from affected groups. This article starts with a short introduction to both historical and contemporary Slotervaart, then outlines briefly some key literature on public participation in urban planning, and finally assesses the "Face Your World" participation project in terms of its successes and failures as a public participation project in urban planning. (Contains 5 figures and 4 footnotes.)