Eighty college students mentally rotated 3-D shapes while maintaining a concurrent verbal or spatial memory load to investigate how sex, native language, and college major relate to the cognitive strategies employed during mental rotation (MR). Males were significantly better than females at MR, whereas native language was not related to MR ability or preferred strategy. A significant Sex × Major × Load interaction was found such that males majoring in the physical sciences performed better when primed by a concurrent spatial load as compared with a no-load or verbal load, suggesting their use of a spatially mediated MR strategy. In contrast, males majoring in the social sciences performed better when primed by a concurrent verbal load as compared with a no-load or spatial load, suggesting their use of a verbal/analytic MR strategy. The potential origins of these differences in strategy are discussed in the context of individual differences in brain organization.