Despite widespread adoption of peer-support programs in organizations around the world whose employees are at high risk of exposure to potentially traumatic incidents, little consensus exists regarding even the most basic concepts and procedures for these programs. In this article, consensus refers to a group decision-making process that seeks not only agreement from most participants, but also resolution of minority objections. The aim of the current study was to develop evidence-informed peer-support guidelines for use in high-risk organizations, designed to enhance consistency around goals and procedures and provide the foundation for a systematic approach to evaluation. From 17 countries, 92 clinicians, researchers, and peer-support practitioners took part in a 3-round web-based Delphi process rating the importance of statements generated from the existing literature. Consensus was achieved for 62 of 77 (81%) statements. Based upon these, 8 key recommendations were developed covering the following areas: (a) goals of peer support, (b) selection of peer supporters, (c) training and accreditation, (d) role of mental health professionals, (e) role of peer supporters, (f) access to peer supporters, (g) looking after peer supporters, and (h) program evaluation. This international consensus may be used as a starting point for the design and implementation of future peer-support programs in high-risk organizations.