The promulgation of a new constitution of Kenyan on 31st August 2010 effectively created two levels of government; the national and county governments. Provision of health services is one of the functions that were devolved to the county government amid resistance from the health care workers’ unions. Devolution of health functions was aimed at improving access to more equitable and high quality health services to the Kenyan citizens. The health sector, therefore, embarked on review of the existing policies, legal and strategic framework for health, to conform with and facilitate implementation of the new constitution. This study sought to analyze the effects of devolution on healthcare delivery in Nakuru County. The study employed a quasi-experimental research design to explore the rating of performance of the health care system before and after devolution. Four key domains in the health systems were explored namely, health service delivery, leadership and governance in health, management of human resources for health and health care financing. The target population was the healthcare workers with management portfolios and the sample population was arrived at using stratified sampling method. A questionnaire was used to collect primary data after it was pilot-tested in Subukia sub-county and edited to improve clarity and validity. Descriptive proportions of the respondents and their cadres were derived. Qualitative data was analysed thematically, while quantitative data analysis utilized chi-square tests or Fisher’s exact test, where applicable, as well as factor analysis.