The effectiveness of policy implementation is rapidly becoming a widely researched area in the water sector. Previously, most studies focused mainly on developing technical innovations for delivering sustainable water services and little attention was given to subject areas such as governance, policy implementation, and legislation. Now, water professionals and policy makers are beginning to recognise that efficient services occur when social, political, economic, environmental and technical issues are taken into consideration; hence, subject areas like policy implementation have started receiving attention as well. Thus, many nations such as the UK, Australia, and the USA are constantly aiming to establish best institutional practices for their water sector, while countries such as Nigeria are yet to establish effective policy implementation processes. This research examines the challenge of effective policy implementation in Nigerian urban water utilities. The research showed that policies and legislation developed were of commendable standards, but the implementation process was predominantly hindered by five factors. Hence, these factors will need to be managed actively if the Nigerian urban sector wishes to achieve the intended results from water legislation and policies.