The Bullitt Center, arguably the greenest office building in the world, is certified by the International Living Future Institute having met the Living Building Challenge. The building is designed to capture and treat rainwater for all uses, and handle all wastewater on-site, including an innovative greywater treatment using a green roof constructed wetland and infiltration facility in the public right-of-way. Approval required multiple code waivers but the project was allowed extraordinary flexibility under the Seattle’s Living Building Pilot Ordinance.