The paper gives results of a survey of seven individuals with considerable experience in radon mitigation in school buildings, to determine the costs of radon diagnostics and active soil depressurization (ASD) system installation in schools. The cost data were determined by providing the mitigators with two scenarios of 'typical' school buildings with elevated radon levels. The survey included five work elements associated with conducting radon diagnostics and mitigation in schools: (1) Review Construction Plans, (2) Conduct Diagnostic Measurements, (3) Design Mitigation System, (4) Purchase ASD Materials, and (5) Install and Check Out ASD System. Based on survey results, it is estimated that the average cost of ASD diagnostics and mitigation in a typical school would be roughly $0.50 per sq ft. About 20% of the cost is for diagnostics, and 80% is for installation costs. These costs would be higher in schools with extensive subslab walls, very poor pressure field extension under the slab, and extensive building code and/or asbestos complications.