The netCDF Users Working Group (NUWG) was formed in September of 1992 by interested parties from COMET, Unidata, and FSL (NOAA Forecast Systems Lab). Its purpose is to develop conventions for representing atmospheric science data and members are drawn from various organizations based on their expertise with specific data sets. NUWG conventions identify the minimum set of variables and attributes required to exchange and access common data sets. The group meets irregularly and works to define conventions for major categories of data such as surface observations and grids and also standard representations for information such as station identification and time. Results of the meetings are distributed on the nuwg@comet.ucar.edu mail list and conventions are maintained in the Unidata pub/netcdf/Conventions/NUWG directory. Interested parties may join the mail list by sending a request to nuwg-request@comet.ucar.edu.