In order to better understand the critical issues pertaining to the concept of performance standards for laboratory animal use, the Institute for Laboratory Animal Research Roundtable on Science and Welfare in Laboratory Animal Use held a public workshop on April 20-21, 2015. The purpose of the workshop was to promote the appropriate and responsible care of animals in research, to provide a balanced and civil forum for discussion and collaboration, and to help build transparency and trust among stakeholders. Participants addressed the challenges of defining, developing, implementing, assessing, and validating performance standards to ensure "optimal practices, management, and operations." This report summarizes the presentations and discussions from the workshop.Table of ContentsFront Matter1 Introduction2 Overview of Performance Standards for the Humane Care and Use of Laboratory Animals3 Regulatory and Advisory Perspectives4 End-User Perspectives5 Detailed Steps in the Development and Implementation of Performance Standards6 Reports from the Breakout Sessions7 Sharing Acceptable Performance Standards8 Reflections on the WorkshopAppendix A: Workshop AgendaAppendix B: Biographical Sketches of Workshop Speakers and Organizing Committee MembersAppendix C: Statement of Task