The present study examined the effects of opponent's cooperation and honesty on the cooperation of 80 like-sexed pairs who played 40 trials of a Prisoner's Dilemma Game. Ss faced an opponent programmed by E to be either Honest-Cooperative, Honest-Competitive, Dishonest-Cooperative, or Dishonest-Competitive. Post-game ratings indicated that a majority of Ss perceived the opponent as competitive and honest regardless of the opponent's actual behavior. Ss' perception was significantly associated with their cooperative behavior, with accurate perceivers being less cooperative than inaccurate perceivers. The greater competitiveness of accurate perceivers was tentatively explained as a function of their more extensive use of the cues generated directly by the experimental context.