Each day we are likely to interact with a variety of people, such as friends, relatives, and workmates, each of who has different thoughts and expectations. My research examines how participating in different interpersonal interactions shapes our self-understanding and evaluations of others, with a focus on outcomes related to ethnic and gender stereotyping, prejudice and discrimination. One line of research shows that individuals' stereotype-relevant self-views are shaped by the apparent beliefs of others. Individuals will engage in self-stereotyping when they want to get along with someone who seems to think stereotypes of their group are true, even if doing so may have non-relational negative consequences. A second line of research shows that although people can not consciously control their level of implicit prejudice, this form of prejudice can shift as a function of fleeting interpersonal interactions. A final line of research examines the impact of contact with members of other ethnic groups, and one's own ethnic group, on one's degree of prejudice. Overall, my work suggests interpersonal interactions are a vehicle by which cultural phenomena (e.g., stereotypes, prejudice) become individual thought.