WAJ, with 260,000 customers in the capital of Amman, introduced a corporate GIS to improve efficiency of water/wastewater operations and customer management. The virtually nonexisting address information in Amman necessitated the use of ARC/INFO cadastral basemaps for geographic location of customers, to be integrated with existing customer data banks, developed under Oracle and COBOL. Applications introduced cover customer address confirmation, inspection maps and work order sheets, route planning tools for meter reading, bill distribution and revenue collection, unaccounted-for-water analysis, and sewer connection monitoring. Concrete revenue improvement in the first year of introduction amounted to more than $650,000, and the total improvement potential on recurrent basis is estimated at $2 million per annum, resulting in payback periods for GIS investments of less than two years.