Despite the increasing awareness that sustainability is an issue needing ongoing attention, and despite millions of dollars spent yearly at universities to promote sustainable behaviors, previous research has found college students have primarily a unidimensional understanding of what sustainability encompasses. The current research sought to understand the depth of students' sustainability knowledge at one of the nation's "greenest" campuses and what implications this finding may have on future educational efforts. A representative sample of 779 students at a public liberal arts university were asked to define the term "sustainability" via an open-ended survey question. The survey also assessed students' knowledge of a dedicated on-campus sustainability office and preferred information sources and message channels. Definitions encompassing maintaining the status quo were the most prevalent, followed by definitions stating that sustainability had an environmental component. The least mentioned concepts were those encompassing the social or economic factors of sustainability--despite these factors being often-cited key components of sustainability. About one-third did not know their university had a Student Office of Sustainability. In addition, about 81% did not know that student fees had been supporting that office's $200,000 annual budget since its inception in 2011. Students' preferred source and message channels for receiving sustainability information (i.e., a mix of interpersonal sources and mass media channels) highlight the need for interdisciplinary collaboration and a multidimensional approach in sustainability education. Improvements in message branding and an increase in learning opportunities both inside and outside the classroom are recommended for advancing sustainability education on college campuses.