Although most people are occasionally lonely, others find loneliness to be an enduring problem. Loneliness is often associated with a variety of personality characteristics which interfere with the formation of interpersonal relationships. The interrelationship of shyness and loneliness over time and in response to varying situations was examined in 2 studies. Undergraduates (N=76) enrolled in large lecture courses completed the UCLA Loneliness Scale and the Social Reticence Scale at the beginning and end of a 10-week interval. Undergraduates (N=50) enrolled in small experiential courses designed to enhance interpersonal effectiveness completed the same instruments with an elapsed interval of 7 weeks. In the lecture group, loneliness significantly increased over time, whereas shyness remained stable. Results indicated that shyness was causally linked to the increase in loneliness. Students in the experiential group showed a significant decrease in both shyness and loneliness. Findings suggest that the experiential nature of the classes may require students to surmount their social reticence, because data reveal that the shy subjects exhibited a significant decrease in loneliness. (Author/NRB)