Political issues can influence the delivery of services and other goals, such as environmental sustainability, within municipalities. However, the influence of political factors on the institutionalization of environmental issues within municipalities has not been examined. We investigate these issues using a case study of a South African municipality that has made considerable progress in institutionalizing environmental issues (particularly climate change related) in the last decade, despite a change in political leadership. The presence of the following factors promoted the institutionalization of environmental governance: (a) political champions; (b) networks between the municipality and other organizations and dense networks within the municipality; and (c) benefits for the municipality from environmental actions. Political issues can enable the process of institutionalization (e.g., by stimulating innovation through political party competition) and also hinder it through political instability (which disrupts patterns in champions and networks) and clientelism (which can cause environmental projects to be discontinued).