In 1973, the Technological Institute Library, along with the other science libraries of Northwestern University, began a study of reference use. For each reference request received in the libraries, the date, time, duration, mode, class of question, and user type were noted. These statistics were tabulated and analyzed by computer. It was concluded that the overall complexity of questions asked in a science library is low and that few non-trivial reference requests are received during evening hours. The library is now seeking to replace some of its reference service with other forms of service. (PF)