This guidance provides information to sponsors and nonclinical laboratory staff regarding the management and conduct of pathology peer review performed during good laboratory practice (GLP)-compliant toxicology studies. When conducted, pathology peer review should be well-documented. However, documentation practices during pathology peer review have not been clearly defined and vary among nonclinical testing facilities. This question-and-answer document is intended to clarify FDA’s recommendations concerning the management, conduct, and documentation of pathology peer review.