Demographic aging is examined in selected countries of east and Southeast Asia.  "Among the 10 countries discussed in this article, there is a wide range of experience in the process of aging from the advanced stage reached by Japan to the incipient stage evident in the Philippines.  Although the direction of age structural shift in these countries is consistent throughout, earlier patterns of fertility, mortality and migration dictate differing effects over the 50-year period, 1970-2020.  This is apparent in the behaviour and changing relationships of cohorts passing through the various stages of the life course.  The ultimate phase of the current ageing cycle results in a greatly expanded elderly component which, if the case of Japan provides a precedent, is likely to be further inflated by concurrent increases in life expectancy among the elderly themselves."