This report summarizes research into the current application of fair use to meet the missions of U.S. academic and research libraries. Sixty-five librarians were interviewed confidentially by telephone for around one hour each. They were asked about their employment of fair use in five key areas of practice: support for teaching and learning, support for scholarship, preservation, exhibition and public outreach, and serving disabled communities. Interviewees reported a strong commitment to obeying copyright law; rarely concerned about their own liability, librarians primarily felt responsible for ensuring their institutions were in compliance with the law. Practice varied considerably, from a rigid permissions culture to ample employment of fair use. Interview subjects expressed various levels of certainty about how to interpret and apply fair use. They were aware of the doctrine, of its status as a flexible "rule of reason," and of some general categories of behavior it may protect, but some lacked a reliable, low-risk method of interpretation. Many moved immediately to "risk management" (i.e., strategizing about how to avoid litigation and other negative consequences) without first determining their fair use rights, and many followed arbitrary but familiar quantitative "guidelines" rather than taking advantage of the flexibility of fair use doctrine. Often, interviewees preferred to be guided by the more specific provisions in Sections 108, 110, and 121 of the Copyright Act, even where fair use would permit activities unsanctioned by those exemptions. Many interviewees found the terms of licenses interfered with otherwise acceptable fair uses. Finally, interviewees reported receiving varying levels of institutional support as they puzzled through copyright problems, with some describing university counsel's offices that had little time or ability to help given the range of pressing concerns competing for their time, while others reported having knowledgeable, responsive legal experts located inside the library. Failure to employ fair use affirmatively and consistently impairs the accomplishment of the academic and research libraries' mission. Interviewees described downsizing, postponing, and shelving courses, research projects, digitization initiatives, and exhibits due to costs associated with seeking permission or making what seem to be tedious case-by-case determinations of fair use. Scholars were denied access to materials, or put to considerable hardship, because of constraints interviewees imposed on the use of copyrighted materials. Some interviewees described providing disabled students with lower levels of access than their peers for fear of violating copyright. Materials with inherent flaws (e.g., books with acidic paper, and analog tape and film that will warp and disintegrate over time) and in near-obsolete formats are languishing because some interviewees were not comfortable acting under fair use where other reformatting provisions may not apply. Interviewees were typically aware that they could go further, but felt constrained in exercising fair use in various situations. Academic and research librarians will benefit from deliberation in order to create a code of best practices in fair use for their community. They will also benefit from greater access to legal counsel who are well-versed in copyright, as well as closer scrutiny and negotiation of licensing terms. (Contains 6 footnotes.)