This paper reports on an investigation of both long-term behavior and short-term behavior as these behaviors are related to pre-game orientation toward bargaining in a two-person, mixed-motive game. The following general hypotheses were supported by the data: (1) In an ambiguous situation where bargainers have little empirical knowledge of the adversary on which to base their perceptions or plans long-term characteristics of personality and attitude affect pre-interaction psychological behavior. (2) In the interdependent environment of a mixed-motive game, perceptions of the adversary are related to plans to cooperate or not. How ego expects alter to act may be influenced by how ego wants and plans to behave. (3) When information is provided about some of the adversary's beliefs, and these beliefs are in disagreement with those of ego, stereotypic images of people who hold such beliefs are called forth; these are reflected in ego's perceptions of the adversary.