Trends in age-specific and age-standardized death certification rates from motor vehicle accidents over the period 1950-1990 were analyzed for 48 countries from four continents (2 from North America, 10 from Latin America, 8 from Asia, 26 from Europe, Australia and New Zealand) on the basis of data produced by the World Health Organization mortality database. In most developed western and Asiatic countries, mortality rates increased until the late 1960's or early 1970's, and declined thereafter to reach values often lower than those of the early 1950's, although the number of circulating vehicles has substantially increased over the same calendar period. The extent of the decline was, however, different in various countries, as well as in the two sexes and in various age groups, thus leading to complex cohort and period patterns. In general, countries (like the U.S.A. or U.K.), where the number of motor vehicles had increased earlier, have now comparatively higher rates at younger than at middle and older age, while the opposite is observed in countries with later spread of motor vehicles. Further, there were a few countries, including Kuwait, Venezuela and several other Latin American countries, Australia and New Zealand, and several southern and eastern European countries, with exceedingly high rates from motor vehicle accidents, and where comprehensive interventions on this important cause of death are therefore a public health priority.