In the latest Shoptalk London podcast, C40 Cities’ Executive Director, Mark Watts and David Chipperfield talk to Michael Hammond, editor of the World Architecture News website. The discussion centred on the role that the private sector can and must play in creating more socially and environmentally sustainable cities, as well as the need for cities to enforce stronger planning policies. The Morland Mixité Capitale project, part of Reinventer Paris, is used as an example of the type of public-private partnership that could act as a model for future development. C40 Cities is a membership club that connects more than 90 cities around the world and tackles various issues including climate change, urban policies and the sharing of best practice.