The outstanding challenge to the architects of a modern health care system is the change in patterns of disease and disability that has taken place over the last fifty years or so.
In all except the least developed societies, people are living longer (largely due to a decreased likelihood of premature death from acute, infectious disease, accidents or violence) and modernising their lifestyles to include a higher energy intake - primarily from animal fats, oils and simple carbohydrates; less physical exertion - especially less walking and less manual work, and more stress - rooted in rapid rates of change in the social environment.
Modern patterns of morbidity are directly related to these changes and are manifested in a high - and growing - prevalence of obesity, type II diabetes mellitus, certain types of cancer, hypertension, cardiovascular diseases, venereal diseases, substance abuse, domestic violence, accidents and social displacement.