Doctoral thesis (PHD)Organizational performance improvement is considered a critical requirement for improved water services in the country. This study on organizational performance improvement of urban water supply and sanitation authorities in Tanzania through human resource management was based on a study of Dar es Salaam city, Morogoro and Moshi urban water supply and sanitation authorities with the aim of contributing to ways of improving water supply and sanitation services through human resource management in Tanzania. Both primary and secondary data were collected and analyzed using a combination of qualitative and quantitative methods. The findings of the study indicate that existing organizational performance improvement initiatives in the three urban water authorities were slow in staff recruitment. Findings point to failure of human resource management officers in the three urban water supply and sanitation authorities to successfully put in place and implement effective human resource policies and strategies. Consequently, there has been poor performance of staff in their duties, particularly in the supply of water and sanitation services to the public. It was further found that there was lack of cooperation between human resource management officers, other employees and customers. To rescue the existing situation the study recommends improved human resource management initiatives in all the three urban water authorities. These include among other things, formulation and implementation of dynamic policies to guide recruitment and retention of skilled staff. This is expected to reduce activities and operational costs thereby improving organizational performance.