Improving the environmental performance of the built environment is a ‘super wicked’ problem, lacking a simplistic or straightforward response. This is particularly challenging where space is rented, in part because the relationships between the various owners, users and managers of the space is regulated – at least in a formal sense - through the lease. Traditional leases largely ignore environmental considerations and present barriers to making energy efficient upgrades. Leasing practices are evolving to become greener. Evidence from a Sydney Better Buildings Partnership (BBP) study, Australian leasing experts, a UK commercial lease study and a case-study of a major UK retailer, Marks and Spencer (MandS), suggests an increasing, trend towards green leases in most of these markets and opportunities for improving environmental performance through green leasing. Further research is needed in both countries to understand the impact that greener leasing has on environmental performance of buildings.