Objective: The aim of this study was to explore how mothers discovered that their children had been sexually abused. The exploration included learning from whom or in what ways mothers learned about the abuse, whether there were prior suspicions, if actions were taken to determine likelihood of abuse, and the barriers to recognizing abuse. Method: An exploratory survey of 125 nonabusive mothers of sexually abused children in three clinical sites was used. The sample included primarily Caucasians and African-Americans in a Midwestern state. A focus group study was used to develop the instrument. The survey was analyzed using descriptive statistics. Results: Mothers first came to learn of sexual abuse from a verbal report (42%) or behaviors (15%) of their victimized child. Almost half of the mothers had a sense that something was "not quite right" prior to knowing about the abuse. Mothers took many actions to try to clarify what was occurring including talking with their child (66%) or watching things more closely (39%). Evidence most convincing mothers of the abuse included child's disclosure (74%), child's behavior (66%), and child's emotions (60%). Factors increasing uncertainty included denial by the abuser (21%). Conclusions: This exploratory study provides initial data on how mothers come to learn of and believe the sexual abuse of their children. Educating mothers about effective ways to explore suspicions and weigh the evidence for or against abuse may enhance maternal protection and expedite investigations.