Abstract. This exploratory paper introduces the notion of the "green" prison, uncovering the ways in which environmental sustainability inflects carceral policies and practices. Focusing on the United States, it highlights the construction of an "organizational sustainable development" discourse within the correctional system, and argues that it is the system, rather than the environment, which is being "sustained", through the promulgation of a "green" prison discourse which serves to deflect attention from the mounting human and financial costs of mass incarceration. It examines the ways in which "sustainability" plays out in correctional facilities, narrowly structured around compliance with "green" environmental and energy-related regulations, and the provision of "green-collar" training for inmates. Drawing on architectural geographies and notions of therapeutic landscapes, the paper theorizes an alternative interpretation of the "green" prison as a nurturing environment, but argues that this model functions only in decarcerative settings imbued with a rehabilitative, rather than a retributive, atmosphere.