Pairs of subjects classified as high or low in dispositional social anxiousness interacted in the presence of noise that they believed would or would not interfere with their ability to interact and form accurate impressions of one another. As predicted by the self-presentational theory of social anxiety, subjects were less aroused (as measured by changes in pulse rates) when they were told that the noise would interfere with their conversation than when they believed it would not, and this effect was strongest for dispositionally socially anxious subjects. Presumably, knowing that other interactants might attribute their social difficulties to the distracting noise reduced self-presentational concerns and social anxiety. Believing that the noise was interpersonally debilitating also eliminated dispositional differences between high and low socially anxious subjects' self-presentations to their conversation partners following the interaction. © 1986.