There is a common notion that creating change in public space is a long and difficult task. That may be true, but it’s no fun. 72 Hour Urban Action offers an innovative platform that encourages rapid change through human initiative and creativity. 72 Hour Urban Action is a competitive architectural festival that generates interventions in public space within an extreme deadline, a tight budget, and limited space. 120 international participants working in 10 teams have 3 days and nights to design and build their projects in the public realm. The teams design, build, work, sleep, and party on site, enriching the city with a multi-cultural and multi-disciplinary experience. Halbrecht’s talk introduces 72 Hour Urban Action, which invites professionals and residents to become active agents of change, from the bottom-up, and to leave a lasting impact on the urban landscape.