Although distribution fitting methods abound in the statistical literature, very few of these methods are found in the major statistical packages. In particular, SPSS (1975), BMD-P (1981) and SAS (1979) only give some overall tests for normality. There a few specialized distribution fitting packages. The distributions the authors have chosen for DISFIT include some of the classic ones as well as those pertinent to the environmental field. The analysis of both environmental monitoring and environmental health data require distribution fitting programs. The DISFIT system is written and programmed in three separate parts. The first part fits discrete distributions, and is available as a technical report (Hasselblad, Stead and Anderson, 1981). The second part fits continuous distributions. This program is available, and the report describing the program should be available by the end of 1982. The third part will fit grouped continuous distributions.