This article presents a revision of a system for classifying examination findings, laboratory findings, and children's statements and behaviors as to their possible relationship to sexual abuse. The revisions are based on published research studies and current recommendations from the American Academy of Pediatrics Committee on Child Abuse and Neglect, and the American Professional Society on the Abuse of Children. Part 1 of the classification system lists genital and anal findings that can be considered normal or nonrelated to abuse, nonspecific for abuse, concerning for abuse, and clear evidence of blunt force or penetrating trauma. Under Part 2, the overall classification of the likelihood of abuse is broken into four categories: no evidence of abuse, possible abuse, probable abuse, and definite evidence of abuse or penetrating trauma. Cautions in the use of the classification system, as well as controversies concerning a few medical findings, are discussed.