The Belgian Breast Cancer Screening program has been launched in 2002 according to the recommendations and quality assurance guidelines of the European Union. Women in the age range 50–69 years are invited to pass a mammography which is read by two independent radiologists. In case of discrepancy, a third reading is requested. Each reading is documented in detail. In the absence of a nationwide central support computer system, a novel Web-based computer system was designed and developed to support the program. The Web site is hosted on a Web server running Windows Server 2003 with Internet Information Server 6.0 and uses ASP technology from Microsoft. Patient data and readings results are entered from the Web site and are stored in an SQL Server database. The support system developed bears all the advantages of Internet-based facilities (e.g., low cost, remote data entry, flexibility, work comfort, ubiquitous access, user friendliness and advanced technology). Difficulties related to graphical data entry on Web pages were smartly resolved. A comprehensive algorithm for comparing mammography readings has been implemented in the system, enhancing the quality of the screening program. The application has been tested and implemented in the Province of Luxemburg, a widespread rural region particularly suited for Internet solutions in preventive medicine. More recently and with little efforts, the application was extended to the Province of Namur. The Web-based system provides management facilities, ubiquitous online statistics, and builds up a reservoir for official statistics and scientific research. As the application is concerned with sensitive medical data, special attention has been paid to provide a maximum of security. Administrative and medical personnel have expressed their total adherence to the system, while local health authorities have used it to justify their involvement in the screening program. Currently, the database for the Province of Luxemburg contains 25,321 women with a mean age of 59.5 ±6.1 years (range: 50–70 years). The participation rate amounts 17.2%, about twice as much as in the other provinces. After the first mammography reading, 20.4% of the women were found to be positive, but this figure dropped to 10.2% after the second mammography reading. The overall disagreement rate between the first and second readings currently amounts 19.7%. It follows that a third reading is required in about 20% of the cases. Statistical analyses have shown that Cohen's Kappa agreement coefficients between radiologists range between 0.37 and 0.70. The application has been running for two years with success to the satisfaction of managerial and medical personnel as well as of provincial public health authorities.