In a developing country with an average life expectancy of 50 years or higher (an age already reached by several less developed nations) unl imited procreation is no longer necessary to insure the survival of 1 or 2 sons. Data from Pakistan computed from the Population Growth Estimation Experiment of 1962-1965 shows that the male mortality ratio for infants under 1 year was 232/1000 but for 1-4 years it was 25/1000 and for 5-14 years 3/1000. Further study showed that women had an average of about 5 living children and some of these children already had children of their own as a result of early marriage. If a 27-year-old father has a 2-year-old son there is a 77.2% chance the child will survive him. If replacement is permitted in case of death a campaign of "at least 2 sons" would result in Pakistan of an average family size of 3.6 children far fewer than is now the case. This strategy should be more acceptable to parents than the present recommendation to restrict the number of children to 2 or 3. There also needs to be economic incentives for small families. Under present conditions the cost per child is small to the average rural family and the reward in prestige is great. The Peoples Republic of China has used negative incentives effectively. Positive incentives should be just as effective but they must be high enough to offset the current rewards of childbearing. There is also need to find out why so many couples do not practice family planning even though they approve of it and how administrative structure influences the success of a program. It has already been shown in Pakistan that repeat visits bring in far more acceptors than just 1 visit and repeated personal contacts should be maintained with the target population.