This article presents an assessment of one of the earliest greywater reuse (GWR) experiences in Sharjah, United Arab Emirates (UAE). In 2003, the Sharjah Electricity and Water Authority (SEWA) imposed a compulsory GWR program on various categories of new buildings in the city. However, implementation of the program faced significant resistance and setbacks and remained limited to about 200 buildings, representing less than 2% water savings. In the analysis presented in this study, the need for GWR was assessed through analyzing SEWA's water supply and demand projections, conducting a 12-month water use survey of 285,000 Sharjah residents from about 140 nationalities, and identifying the areas in the city with intense water use. In addition, analysis and reforms of the various aspects of SEWA's GWR reuse policies and practice were presented and discussed. Reforming the policy to increase GWR to about 10% water savings can lead to significant reductions in desalinated water consumption and wastewater generation and consequently significant reductions in desalination cost (35 million USD/y), energy consumption (225,840 MWh/year) and CO2 emissions (120 ton/year). The case study presented in the article can serve as a reference to guide GWR policies and practice, especially for local authorities in developing countries.