Ten introverts and 10 extraverts were selected from a student population on the bask of their responses to the E.P.I. The groups contained 5 men and 5 women and were matched for Neuroticism. Each subject took part in two 4-minute conversations, one with a male confederate, one with a female confederate. The same two confederates were used throughout the experiment, and no attempt was made to programme any aspect of their behaviour. Two trained observers, who sat behind a one way screen situated close to the speakers, recorded the visual and speech behaviour of both subject and confederate by means of a four-channel event-recorder. The recordings were made for the last 3 minutes of each interaction. Extraverts Looked more frequently than introverts, but there were no differences between the two groups in the proportions of time spent in Looking and eye-contact, or in the mean length of Looks. Extraverts also spoke more frequently than introverts, a finding which may complement that for the number of Looks. The findings could not be explained by the behaviour of the confederates, since they behaved consistently across the two groups of subjects. The experiment is discussed with particular reference to Mobbs (1968) and Kendon and Cook (1969). Comparisons of methodology are made.