On November 9, 2006, a resolution was introduced at a meeting of the Cornell University Student Assembly (SA) requesting that Cornell University Library (CUL) officials extend the hours of Olin Library to correspond to those of Uris Library, and to extend services at both libraries to include stack access for all hours the libraries are open. In order to assist in the formulation of a response to this request, Research and Assessment Services was asked to prepare a background paper on extended library hour services at peer institutions. This report is the result of that request. The study revealed that the degree of service requested by SA, involving nearly round the clock access to two major library facilities and their stack collections, is beyond what is provided even at peer institutions known for high level extended hours provisions. However, it also suggested that the services currently offered at Uris Library fall short in some areas, particularly in terms of operating hours during reading and exam periods, and collection access during the overnight period.