Sustainability is a fast evolving movement in higher education demonstrated by a proliferation of academic programs and co-curricular initiative and projects. After a review of sustainability-related LibGuides (online resource guides) created by academic librarians, a survey was administered to their developers during the spring of 2011 and posted on library listservs. Librarians returned 112 survey responses which reflected active roles in the paradigm shift toward sustainability through the forging of partnerships across campus and development of teaching resources and events. Telephone interviews conducted with 24 of the respondents showed librarians’ wide-ranging personal and professional interest in sustainability, and their initiatives to promote its cause, including creating resources, collections, exhibits and events; library instruction; co-teaching with faculty; serving on sustainability committees, and collaborating with sustainability faculty and staff. A case study of the engagement of University of Massachusetts Amherst Libraries with campus sustainability initiatives as well as the author’s professional development activities shows that librarians promote sustainability in numerous ways on their campuses and through professional associations. However, both the survey and the interviews suggest that librarians often lack contact or knowledge of work undertaken elsewhere. Moreover, as the needs of students and faculty studying sustainability increase, libraries should appoint librarians with special responsibilities in this field.