The National Police Service held a vital mandate in preserving public order, safeguarding citizens, and protecting national security. Despite this, the NPS had encountered numerous challenges that hindered effective service delivery. These challenges included increased criminal activity, dwindling public confidence, inefficiencies in operations, and limitations in resource allocation. This study examined how change management practices influenced the quality of service delivery within the NPS, focusing specifically on Nairobi County in Nairobi County, Kenya. The study investigated the roles of employee participation in decision-making, strategic communication, leadership support, and capacity building in improving service outcomes. The research was anchored on Lewin’s Change Management Theory, Human-Based Theory, Chaos Theory, and the SERVQUAL model. A descriptive research design was adopted, targeting 150 police personnel in Nairobi County. Due to the manageable population size, a census method was employed, with data collected from senior, middle-ranking, and junior officers using semi-structured questionnaires. A pilot test involving 15 participants was conducted to assess validity and reliability, with a Cronbach’s Alpha score above 0.7 confirming reliability. Quantitative data were analyzed using descriptive and inferential statistics, while qualitative data were examined through content analysis. The findings revealed that employee involvement in decision-making, effective resource allocation, structured organizational communication, and supportive leadership positively influenced service delivery within the NPS. Employee participation enhanced accountability and acceptance of change initiatives, while adequate financial, human, and technological resources improved efficiency. Communication practices provided multiple channels for information sharing, although gaps in one-on-one communication and information accessibility remained. Leadership played a moderate-to-high role in championing change, though the need for greater officer support and individualized consideration was highlighted. Service delivery outcomes showed improvements in operational efficiency and response time, though public satisfaction remained moderate, reflecting the need for enhanced citizen engagement.