Few studies so far have investigated whether abrupt social changes in a society affect the development of friendship and moral reasoning. In this study, 2 cohorts of 188 East German children and adolescents (aged 7, 9, 12, and 15 years) were interviewed in 1990 and 2005. Participants were asked about the importance of close friendship (friendship concept) as well as their moral decisions and reasoning in a friendship dilemma. Overall, results show that in 2005, East German participants referred to normative and interpersonal-altruistic-empathic concerns significantly more often than participants interviewed in 1990. Reference to relationship concerns decreased from 1990 to 2005. With few exceptions, these cohort effects were equally found in younger (children) and older (adolescents) age groups.