The decline in mortality from coronary heart disease (CHD) in several countries, notably the United States, in the 1970s has drawn attention to the need for monitoring secular trends in mortality and morbidity from this disease internationally and to discover the reasons for any upward or downward changes. Mortality trends for CHD in 27 countries are seen to vary widely, being very similar for men and women. It is, however, important to view CHD not in isolation but in terms of total mortality (TM) and other specific causes of death. For a more comprehensive picture, it is also necessary to go back two more decades into the 1950s, requiring the use of a broader diagnostic category "nonrheumatic and hypertensive heart disease" (HD). Using examples from selected countries, it is shown that CHD and HD run generally in parallel, that HD trends often though not always determine TM, and that cancer trends may or may not follow those for HD. Since preventive measures for CHD are likely to be beneficial for the prevention of other diseases as well, the concomitant study of trends for several chronic disorders ought to be rewarding.