How interracial contact affects the attitudes of blacks towards whites is explored in this study, which also delineates the personality characteristics predictive of prejudice and prejudice changes, and how these characteristics differ between blacks and whites. The sample includes 112 male inmates; 63 blacks and 49 whites, who are newly admitted to a medium security correctional institution. Over a one month period every inmate takes a series of questionnaires to assess his cognitive complexity, self esteem, attitudes toward people, and prejudice. Three weeks after his first session each then responds to a second measure of prejudice. Results indicate that initially whites are much more prejudiced than blacks. The contract situation increases prejudice in blacks and decreases it in whites. The only variable that functions the same for both races is that within each group positive attitudes toward people in general predicts a decrease in prejudice. Simple cognitive structure, highly predictive of prejudice in whites, is predictive of a low level in blacks. Low self esteem predicts a decrease in prejudice in whites, but an increase in blacks. The implementation of contact situations without adequate insight into the effects on both races is cautioned. (Author/AM)