The Reppy Institute received early funding from the Ford Foundation, and in 1978 a second major grant from Ford was used to establish an endowment. Income from the endowment, supplemented by an annual operating grant from the university, supports the core activities of the Institute. In recent years these funds have been augmented by an institutional grant from the John D. and Catherine T. MacArthur Foundation and by individual research grants from the Carnegie Corporation, the United States Institute of Peace, MacArthur, Hewlett, and other foundations. In 2000 two program members were among only 12 U.S. researchers in the first class of Carnegie Scholars (a fellowship program of the Carnegie Corporation of New York).
The establishment of the Marion and Frank Long Endowment Fund in 1993 was a step toward building support for graduate education on a permanent basis. Income from the fund is used to provide graduate fellowships for students in peace studies, with the first award being made in 1995-1996. The Reppy Institute has been able to expand its support to graduate students with the Bluestone Peace Studies Fellowship.
A bequest from Harrop and Ruth Freeman established an endowment in 1995 to continue to support the Harrop and Ruth Freeman Prize in Peace Studies. The Freemans established the prize to offer recognition and encouragement to Cornell students actively engaged in promoting peace. The award is given each spring to graduating seniors.