A test model of a computer-off-line system at the Community Hospital Blood Bank in Herford collecting approximately 3.000 units of blood annually is described. The computer system presented, now in operation for more than one year, has proven its value for general blood bank administration by its time-saving effect and the optimalized documentation of donor- and blood-related data. The computer system described is particularly recommended for smaller, hospital-based blood transfusion services. Its introduction is even justified in institutions preparing less than 5.000 units of blood per year. Prerequisite for an economical operation of the computer system is the participation of the hospital management in other computer activities, i.e. book-keeping, accounting etc.