For banks, net zero means much more than just limiting the emissions caused by their own operations; it includes helping customers transition to net zero too. The former is difficult enough. The latter includes a number of big challenges, just the first of which is the assumption of more risk than banks are designed to cope with: funding a new green economy, with all the unfamiliarity and new infrastructure that entails, takes banks beyond their mandate of lending their customers’ deposits prudently. Added to this is the fact that few banks have the data, and the data management capability, to assess which customers they should lend to and how effectively these loans are being used. They also lack the expertise to help customers transition from ‘brown’ to ‘green’ organizations, a transition that's different for every industry—and most players within each industry. The majority of large banks have accepted these challenges, but they have much to do if they are to overcome them.