The transfer of medical records from a paper system to a computer-based system is inevitable. However, the widespread acceptance of electronic medical records has been delayed by problems such as high cost, inefficiency, data entry errors and poor physician acceptance. We have developed a database system that has overcome these difficulties and now serves as an electronic medical record. Our system has been in use for a year and a half, and currently contains information on over two thousand patients. The database provides an electronic radiation oncology chart containing patients' demographic information, technical treatment data and dictated reports. All dictated notes are captured, including consultation notes, treatment summaries, on-treatment visits, letters and follow up reports. The system provides data validation upon entry, required few additional software or hardware purchases, and allows for efficient retrieval of data. Unlike other database systems which require the hiring of data entry clerks to input the data, ours combines transcription and data entry. The database runs on a local area network of computers and uses a commercially available relational database package. It makes extensive use of mouse interface features such as pull-down menus, pop-up lists, buttons, multi-page forms, and scrolling fields, making the system easy to use with minimal training. Many custom features are built in, such as help screens, control functions, audit trails, and a system that keeps track of each patient's referring and other relevant physicians. For research purposes, the system has the capability to perform survival analyses on arbitrary user-defined subsets of patients. Data may also be exported transparently to statistical packages for other types of analyses.