Until recently, age trends in suicide rates followed the pattern of the lowest rates appearing among the young and the highest among the elderly. In recent years, this pattern changed substantially. The pattern of a gradual rise in the incidence of suicide from youth to adulthood shifted to a pattern of sharp increase to the early twenties, slightly lower rates through middle age, and an increase to higher levels only among those in their seventies. Suicides among children reached unprecedented levels. It is suggested that these changes can be explained by the extent to which members of birth cohorts experience social integration and regulation. Data came from publicly available government documents and describe the population of the United States born between 1915 and 1995. Results show that independent of age and period, and with an implicit control for the linear effect of cohort time of birth, cohort characteristics that were theoretically related to integration and regulation had substantively strong and statistically significant relationships to age-period-specific rates of suicides. Members of cohorts that were relatively large and that had larger numbers of non-marital births were at higher risk of both suicide and homicide. These cohort characteristics are associated with the recent upturn in youth suicide and homicide rates. These cohort characteristics, which are theoretically related to less integration and regulation, are associated with higher suicide rates throughout the life cycle, at least for the age groups examined: 10-14 to 75-79. It is reasonable to surmise that sharp changes in family structure are most responsible for recent strong increases in youthful suicide, while increases in relative cohort size account for the more modest increases in youth suicide observed in earlier periods, particularly 1960-75. These findings parallel other findings within the general tradition of cohort research that indicate ways in which formative experiences can produce lifelong effects. 3 figures, 3 tables, 28 notes, 98 references