OBJECTIVES: Child sexual abuse (CSA) is considered a major risk factor for a variety of health problems both in childhood and in later adult life. While population-based surveys aim to establish the real incidence rates of CSA by interviewing potential (past) victims, agency surveys focus on the rates of CSA reported to the authorities. METHODS: We conducted a nationwide agency survey of CSA in Switzerland. Data were collected from 350 agencies through an anonymous online form during a 6-month period. For data collection, we used a modified version of the case reporting form translated from the American National Incidence Study (NIS-4). RESULTS: About 2.68 cases of CSA per 1,000 children per year are disclosed to agencies (1.11 in males, 4.33 in females). This is roughly twice the average incidence rate reported in methodologically similar studies from Canada, the US, and Australia. CONCLUSIONS: In Switzerland, the majority of disclosed cases of CSA are handled by specialized yet semi-public agencies instead of public child welfare agencies or penal authorities. This fact might explain the higher disclosure rates.