Pathology peer review is the process by which a separate pathologist reviews the pathology report, ancillary data, and a subset of the slides to verify and improve the accuracy and quality of pathology diagnoses and interpretations. It may also be added to a study to address specific questions from Sponsors or Regulators. This presentation is geared for toxicologists and will address: 1) how pathology peer review can add value to nonclinical safety studies, 2) the basic "best practice" methods of pathology peer review, and 3) recent guidance from the FDA on what constitutes a GLP-compliant pathology peer review.