The Flexible Regional Emissions Data System (FREDS) for the 1985 NAPAP Emissions Inventory extracts emission data, pertinent modeling parameters and source identification information from point and area source data (contained in processed SAS files) and applies appropriate temporal, spatial, and pollutant species allocation factors to derive a gridded, speciated, and temporally resolved emissions file suitable as input to regional scale atmospheric simulation models. FREDS consists of seven modules which are used to reformat the data, apply allocation factors to the annual emission data, and ensure the quality of FREDS output. The seven modules are the hydrocarbon preprocessor, the quality control module, the model data extraction module, the temporal allocation module, the speciation module, the spatial allocation module, and the model input preprocessor. Many of the modules can be implemented in a logical sequence or independently of the others in most cases. To maximize flexibility, FREDS allows the user to define and assign emissions of up to 15 pollutants prior to speciation, the temporal scenario, spatial grid origin and grid cell size, and the number and relationship of pollutant subspecies. Software description: The model is written in the FORTRAN and SAS programming languages for implementation on an IBM 3090 computer using the OS/TSO operating system.