AbstractAs suggested in the computer note printed in this journal in March‐April 1993 and titled “United Nations Ground‐Water Software,” to which this note is a sequel, the Windows version is completed and ready for distribution. The software, known as Ground Water for Windows (GWW), is the United Nations contribution to the ground‐water data information processing and management. GWW is flexible, user‐controlled, sophisticated, and versatile. It is an object oriented, relational data base and tailored for use as a ground‐water information system (GWIS). The software integrates classical ground‐water information (lithology, hydrographs, chemistry, pumping tests, etc.) with geographic displays. The software is programmed as a Windows application, and it uses all Windows resources: memory management, fonts, colors, screen, printer, and plotter drivers, etc. It is input and output device independent, and has no memory limitations except for the ones that are intrinsic to any Windows application. The data base can be filtered; that is, a large set of information can be reduced to subset having user‐selected attributes on any part of the data. The user designs the structure of the data base and creates entry and reporting forms. The software is primarily intended for the creation of large relational data bases on a site, region, province, county, or country wide basis.In addition to ground‐water data processing, GWW has its own powerful mapping utility. Various location and thematic content maps become an integral part of the ground‐water base. The exchange of information with other software packages is enabled via import and export of AutoCad's DXF and ASCII files.Following the philosophy that a picture is worth a thousand words, GWW emphasizes graphics on screen and printed in: maps, logs, cross sections, hydrographs, various chemical diagrams, etc. The current version of this software is in the public domain and is available through the United Nations for the developing world or through educational courses for the developed world.