Social participation, defined as socially oriented sharing of individual resources, is often regarded as an important criterion of quality of life in old age. We distinguished three types of participation with respect to content, context, and resources required to participate: collective, productive, and political participation. Data from the multidisciplinary Berlin Aging Study were used to describe social participation of a very old population and to examine individual differences and changes over time. Analyses showed that social participation is cumulative. Individuals who engaged in political activities also took part in the other two types, and those who engaged in productive activities also participated in collective activities. Although many persons changed their social participation over the 4-year period, the cumulative pattern within the population remained unchanged. Educational and occupational resources were positively related to the intensity of social participation in old age, but changes in social participation could be better explained by age and health.