Facing steep budget cuts and rising energy costs, many colleges are grappling with how to finance urgently needed, but capital intensive, energy efficiency upgrades on campus. One innovative approach, using return-oriented green revolving funds (GRFs), is a rapidly growing trend at colleges and universities. GRFs can invest in a variety of cost-saving initiatives, resulting in significant financial and environmental benefits. "Greening the Bottom Line" brings to light current trends based on the first survey ever conducted about GRFs in higher education. Green revolving funds invest in enhancing energy efficiency and decreasing resource use, thereby reducing operating expenses and greenhouse gas emissions. The cost savings boost the bottom line and replenish the GRF for investment in the next round of green upgrades. To better understand the emerging trend toward the creation of more GRFs, the Sustainable Endowments Institute conducted a survey of green revolving funds in 2010. "Greening the Bottom Line" examines and evaluates the results of this survey of 52 institutions with at least $66 million invested through GRFs. SEI's survey included schools in 25 U.S. states and 2 Canadian provinces with 24 public institutions and 28 private institutions represented. Funds range in size from $5,000 at the College of Wooster (Ohio) to $25.45 million at Stanford University, with an average size of $1.4 million and a median size of $170,000. Approximately 35 percent of funds are $100,000 or less, and over a third of institutions with GRFs have endowment assets of less than $250 million. An institution does not have to be affluent to create a GRF. Based on survey data from funds at 52 institutions, the following key findings emerged: (1) The number of GRFs is growing rapidly, with nearly three quarters created since 2008; (2) All sizes and types of institutions are creating GRFs; (3) The GRF model is universally customizable to meet a range of institutional goals; (4) GRFs help schools advance other goals such as academic, co-curricular, and campus community engagement on sustainability issues; and (5) Reports to date suggest potential for consistent annual returns ranging from 29 percent (Iowa State University) to more than 47 percent (Western Michigan University). Given these findings, this report aims to: (1) Provide basic information on the formation, operation and performance of GRFs to help institutions that are interested in establishing their own; (2) Enable institutions that have GRFs to learn from each other's experiences; and (3) Create a baseline for tracking the continuing emergence of GRFs in higher education. Appended are: (1) Methodology; (2) List of Green Revolving Funds; (3) Sampling of Green Revolving Fund Projects; (4) Areas for Further Study; (5) Key Statistics about Green Revolving Funds; and (6) Further Reading. (Contains 8 exhibits and 14 footnotes.) [Contributing authors include Julian Dautremont-Smith and Mark Orlowski. Funding for this paper was provided by EPA's Green Power Partnership, HOK, Roy A. Hunt Foundation, National Wildlife Federation's Campus Ecology and GreenerU.]