This research paper presents a comprehensive overview of paradigm shifts in public administration over time and their implications for public service delivery. The paper starts with the Old Public Administration and moves into the New Public Management. It then delves into post-NPM trends, including the New Public Service, New Public Governance, Public Value Management, Digital Era Governance, and the Whole of Government approach. Each paradigm is discussed in detail, highlighting its unique features and their effects on public service delivery. Overall, this paper makes a significant contribution to the field of public service, offering valuable insights for policymakers, administrators, service providers, scholars, and practitioners.