This analysis of the Monitoring the Future survey of the high school seniors in 1975 focuses on measurement and correlates of prosocial concern. The data base allows for an exploration of the following: (1) the concept of concern for others; (2) its predicted interrelationships with attitudes toward social problems; and (3) the causes of such concern and possible modifications through actual experience. The development of a constructed index of concern is presented, and relationships with various social attitudes are examined. As predicted, positive racial attitudes, support of equal rights for minorities as well as women, and concern about pollution are related to "concern for others." Young women, seniors with high self-reported abilities, and those with an interest in government tend to score highly on the index of concern. Actual reported behavior, as in race relations or conservation efforts, is more weakly related than attitudes, a finding attributed to seniors' limited control over their lives, and the generally weak correlations between attitudes and behavior. (Author/APM)