In this paper we present two studies concerning the application of a virtual environment for public speaking anxiety. We have created a program simulating a virtual lecture room, which can be filled with a large number of listeners behaving in different ways. The purpose of the scene is to train people who are anxious to give talks in front of a large audience. We present the results of two studies, showing the impact of this kind of virtual exposure. Results indicate that people do experience such a situation as realistic, as well as report social insecurity and show heightened psychophysiological arousal (HR). Furthermore, we show that especially curious people, and people with high social insecurity rate the system as useful.