Portland joined Philadelphia and Amsterdam as the first cities to pilot the Thriving Cities Initiative. The Initiative is a collaboration between C40, the Amsterdam-based Circle Economy, which seeks to create zero-waste urban economies that support their residents, and the Doughnut Economics Action Lab, an organization mostly comprising volunteers working to implement systemic, society-wide economic change. At its most basic level, doughnut economics is a way of describing an economic system that extends beyond strictly financial measures, like gross domestic product, to include environmental sustainability and healthy, thriving communities. The Thriving Cities Initiative's model - and the expertise and resources it provided - dovetailed with Portland's existing momentum in tracking and reducing emissions that accounted for spending by government, businesses, and households. The model also pointed to ways to address the city's social issues, including more than 4,000 people in the metro area without stable housing. The pandemic ... forced Portland to scale back its Thriving Cities program. A five-year program that could have formed the basis for city council action was scaled back to a two-year in-house plan that the city's Bureau of Planning and Sustainability could follow on its own. Still, some existing programs already were in line with the goals of the Thriving Cities Initiative. In Amsterdam, the Doughnut Coalition and the city government are already looking toward next steps.