The Virtual Environment Performance Assessment Battery (VEPAB) is a set of tasks developed to support research on training applications of virtual environment (VE) technology. VEPAB measures human performance on vision, locomotion, tracking, object manipulation, and reaction time tasks performed in three-dimensional, interactive VEs. It can be used to provide a general orientation for interacting in VEs and to determine both entry level performance and skill acquisition of users. In addition, VEPAB allows comparison of task performance, side effects and aftereffects, and subjective reactions across different VE systems. By providing benchmarks of human performance, VEPAB can promote continuity in training research involving different technologies, separate research facilities, and dissimilar subject populations. This paper describes the development of VEPAB and summarizes the results of two experiments, one to test the sensitivity of the tasks to differences between input control devices and the other to examine practice effects.