Green building—the construction of buildings designed to minimize environmental impact and resource use—has become significantly more common in the past decade. Many local and state governments have enacted policies designed to stimulate green building. These policies generally include information provision, subsidies for private green development, and outright greenness requirements for all government buildings. Despite this growing commitment from government, as well as substantial evidence that green buildings are financially beneficial for private owners, the private sector has been slow to embrace green building. This Note argues that barriers to innovation in the real estate industry have rendered ineffective these local government attempts to stimulate green building and suggests that impact fees—fees imposed by local governments on land use development—will be more successful in pushing private real estate developers to build green. Although the use of these fees is subject to both state and federal constitutional constraints, an appropriately designed fee can maximize the effectiveness and efficiency of this proposal while also ensuring that the fees are constitutional.