DATMAN is a data management system which runs on a variety of minicomputers. Currently, versions are supported on the following computers: PRIME and PDP 11/70 under IAS. DATMAN has facilities for creating data bases, retrieving selected data from data in data bases, retrieving selected data from data bases and processing the retrieved data. Access through DATMAN is either through a terminal interface with which the user executes DATMAN directly or through a FORTRAN interface within which the user calls FORTRAN subroutines to access DATMAN data bases. This manual is intended to describe the FORTRAN user interface.