Seventy-two Sprague-Dawley rats were used to investigate the multidimensional features of the context shift effect and the forgetting of stimulus attributes in a Pavlovian differential fear conditioning paradigm. One day after training, a change in either conditioning box or room context resulted in substantial decrements in performance similar to that induced by a shift of both box and room contexts. Two weeks after training, a shift of either box or room context exerted no significant detrimental effects on responding. However, a combined shift of both box and room contexts still induced a severe performance deficit. These results suggest that changes in various components of the stimulus context can result in similar retention deficits, that several aspects of stimulus attributes are forgotten over a delay, and that changing several aspects of the stimulus complex can synergistically impair performance.