We investigated sustained departmental change catalyzed by three Departmental Action Teams (DATs) that worked on change projects independently following an initial period of external facilitation. Using qualitative analysis of interview data, we documented four main categories of change catalyzed by DATs, three categories of supports for change, and four categories of constraints on change. DATs accomplished a wide variety of sustained changes, and DAT members frequently leveraged their individual learning to benefit the work in departmental groups outside of their DAT. Change was documented at the levels of the individual, the group, and the organization (i.e., department or university), suggesting that the DAT model is capable of supporting organizational learning at all of these levels. Additionally, DATs successfully used levers of project prioritization and positional power to generate sustained change. DATs did not rely heavily on support outside of their departments to accomplish sustained change. This study provides insight into the mechanisms by which departmentally based change teams accomplish change in departmental cultures, practices, and processes influencing science, technology, engineering, and mathematics education.