Health promotion can reasonably be viewed as a major element in public health work. The latter was defined around a century ago as "the science and art of preventing disease, prolonging life and promoting health through the organized efforts of society." Health promotion involves (i) health education, such as advertising; (ii) illness prevention, such as screening; and (iii) legislation, such as banning smoking in public places. Although it has older roots, it is largely a phenomenon of the mid-twentieth century and beyond. Three factors stimulated