For the first time in the history of Homo sapiens, we are primarily an urban species: more than half of us live in towns or cities. By 2050, the world’s urban population will swell by almost 3 billion. All this growth will require new infrastructure, as will the challenge of adapting cities to climate change. Ecologists, urban planners, economists and landscape architects are increasingly asked to consider the role that green infrastructure can play in meeting these challenges. Yet guidance on how to plan and execute projects to protect or restore natural infrastructure is often hard to come by. How do you tell which of nature’s benefits are most important for a particular city? How do you map which patches of natural habitat are most important? How should urban planners find the optimal mix of natural and traditional “gray” infrastructure to solve problems? In this talk, Rob McDonald presents stories of cities around the world that have overcome these challenges and reviews the new science that is letting city planners and conservationists begin to answer these questions. - April 13, 2016