What follows is not only a summary of first impressions, but it is also limited to Pakistan as a whole, i.e., inter-regional differentials are not inves¬tigated. Furthermore, the following comments are limited to the youngest ages. In particular, no discussion is offered of the age distribution at the oldest ages. In any case the latter is partly a freak of the peculiar assumption on which it is drawn, namely, that nobody in Pakistan lives beyond the age of eighty. These are very severe limitations and in part what follows is more in the nature of advance notice of research to be undertaken than it is a report on substantive findings. Nevertheless, the initial impressions are of a startling enough nature to justify disclosure at this stage, but on the distinct understanding that they may on further inquiry prove illusory. The observations of this note are based on the simple fact that the population of any area at any time is a function of fertility, mortality and migration prevailing in the past. There are two ways in which these three influences show themselves: on the age distribution and the rate of growth. In a way, it may be more helpful to say that age distribution and growth are the other side of the same thing, namely, the combined product of fertility, mortality and migration. In fact, this is such a wide and all-em¬bracing statement that it may seem almost meaningless. However, relatively recent developments in demographic theory furnish powerful tools for analysis of age distribution and growth. Evidence of growth, such as it is, is not considered in this note. As already indicated, the discussion is limited to age distribution.