The National Geospatial Data Clearinghouse coordinated by the U.S. Federal Geographic Data Committee is a distributed repository of digital geospatial data and its related descriptive information known as "metadata." A growing number of federal, state, and local organizations have implemented local Clearinghouses of spatial data on the Internet using software and guidance provided by the FGDC. Through the use of a standard protocol (ANSI/ISO Z39.50 or "Search and Retrieve"), client software extensions to commonly-available World Wide Web browsers can directly access one or more collections of digital spatial data and download the digital map data. A map query tool has also been designed by the FGDC for public use to assist the user in defining an area of interest by clicking on a flexible map of the world to push coordinate information into the Z39.50 query. This paper discusses the software requirements and environment necessary to establish and use the on-line nodes of the National Geospatial Data Clearinghouse.