VPF supports multiple iterations of interleaved construction and feedback by allowing VH authors to create a basic draft of the VH and then e-mail links for talking to the VH to other users. Interaction with the VH is through a text-based system that is similar to popular instant messaging applications. An example VPF interaction can be seen in Figure 2. VPF has been used to create VH patients that train healthcare professionals with their interpersonal skills. VPF is currently used in four medical schools and has facilitated thousands of human-VH interactions.