A conception of the self system is needed for studying personally involving beliefs and attitudes, particularly to interpret research findings that show differences in cognitive processing and action as a function of varying levels of involvement. Different levels of involvement are associated with different structures of attitudes and beliefs, as well as ratings of confidence, subjective certainty and personal importance. Different attitude structures associated with low or high involvement lead to specific predictions about individuals' construal of events, evaluations of communications, and the likelihood of attitude change. By understanding the structures that compose the self system, different strategies for change are indicated, depending upon the degree of personal involvement, relationships with the communicator, the discrepancy of the communication from the person's attitude, and the ambiguity of the outcome. (Author/NRB)