As the biggest providers of health services, Primary Health Centres play a crucial role, especially in the rural areas. Kerala has gained international recognition for its outstanding achievements in the health sector. The health status of the tribals in many part of India is quite poor, primarily owing to the inaccessibility of their villages to health services and also due to their poor economic conditions. The benefits of modern medicines and the health delivery system have not reached them adequately. The present study is an attempt to identify the factors of utilisation of health services and analyse the extent of health care utilisation. The thesis is presented in nine chapters; (I) Public Health Service --Historical Context (II) Health of Tribals ---An Overview (III) Utilisation of Primary Health Care –-Theoretical Framework (IV) Review of Literature (V) Objectives and Methodology (VI) Problem Setting (VII) Profile of the Sample Households (VII) Utilisation of Primary Health Centre (IX) Conclusions and Recommendations.