The environmental sustainability of museum lighting is placed within the context of wider strategies to reduce the use of non-renewable energy. Various measures to reduce energy and resource consumption are presented, including switching to, or generating, renewable electricity, the installation of more energy efficient and longer lasting LED lamps, increased use of daylight and changes to museum lighting practice that reduce energy consumption. The sustainability of lamps and lighting systems is explored in the respect to the precepts of reduction, reuse and recycling of materials. A method of considering environmental sustainability alongside economic, operational, social and societal sustainability is described. The model is used to assess the impact of the various changes to museum lighting practice introduced to improve environmental performance on these other measures of sustainability, paying particular attention to their effect on social sustainability (defined in terms of current accessibility) and societal sustainability, which encompasses the longer-term preservation of objects.