A Sanitation Master Plan (SMP) was developed for to study and evaluate the existing sanitation system serviced by the Lusaka Water and Sewerage Company (LWSC) to identify sanitation improvements for a 25 year planning period for the City of Lusaka, Zambia. Lusaka, the largest city in Zambia, has a population of more than 1.5 million and a projected population of 5.0 million in 2035. LWSC currently operates 480 km of sewer, 8 pump stations and seven treatment facilities in Lusaka. Approximately 16 percent of the population has household sewer service. The remainder is served by onsite systems, primarily pit latrines. Review of previous studies, review of existing data and plans, field inspections, and hydraulic modeling were used to assess the condition of the existing infrastructure and identify the needs of the sanitation sector. A goal of 100 percent access to improved sanitation by 2035 was established. A total investment need of approximately 1.9 billion dollars was identified over the planning period.