The Pressure Aging Vessel (PAV)is an aging procedure proposed by the Strategic Highway Research Project (SHRP) to simulate long-term field oxidative aging of asphalt binders. The development of the PAV included evaluation of the factors affecting the PAV procedure as well as validation of the PAV as a procedure to mimic field aging of binders. In this paper the research done to evaluate the factors affecting the aging in the PAV and the selection of the operational factors is described. The changes in rheological properties that result from the PAV procedure are also presented and compared with changes resulting from field aging. The results indicate that temperature can be used effectively to accelerate aging in the PAV and that film thickness and time are important factors that need to be carefully controlled. The evaluation of the rheological changes indicates that aging changes the rheological type of asphalts by changing the shape of the master rheological curve while the temperature dependency, as measured by the time-temperature shift function, does not appear to change significantly as a result of aging. The results indicate that the PAV can be successfully used to mimic rheological changes that result from field aging.