Decentralisation, an approach for improved service delivery, has become increasingly popular in developing countries in the recent past, along with the importance given to governance and enhanced citizens’ participation in the decision-making process. This article focuses on the challenges which Lusaka City Council (LCC), the largest council in Zambia with relative capacity to implement Government Policies on time, had experienced during the implementation of the National Decentralisation Policy (NDP). These challenges were noted during an assessment of the extent to which the NDP had been implemented by the Council mentioned above, as of July 2019. The evaluation adopted a qualitative approach. The sample size of twelve key informants and a Focus Group was purposively selected, and the data were thematically analysed. The findings revealed that the failure to fully implement the NDP by LCC resulted mainly from, political interference, inconsistencies in the law, incomplete institutional restructuring, delimitation of political boundaries, resistance by some officers to be transferred to local authorities, and inadequate monitoring and evaluation of policy implementation at all levels of governance and unactualised fiscal decentralization. Thus, LCC had not yet attained full implementation of decentralisation by devolution as of July 2019. These challenges needed to be addressed if the benefits of decentralisation by devolution were to be realised in Lusaka City and the nation at large.