Public Health Medicine focuses on the health of populations. It is concerned with the delivery of healthcare services, health promotion, and the prevention of disease and injury, both within populations at large and within community groups. Although considered a non-clinical specialty of medicine, practice is firmly founded on clinical experience and medical expertise. Public health medicine studies epidemiology, biostatistics, health protection (including environmental health as well as communicable disease prevention and control), and health policy, planning, and management. It recognises environmental influences on health and disease and the importance of scientific evaluation methods. It seeks to assess the health needs of the population in general and of specific community groups and to evaluate the effectiveness of policies and programs. Importantly, public health medicine is involved in research and must consult with a variety of health providers, health boards, hospitals, the public, the government, industry and institutions, to involve them in processes which help to determine the appropriateness, effectiveness and benefits of health services, public health initiatives and government policy.