We here report two studies exploring associations between inhibitory control (measured with the Sustained Attention to Response Task, SART) on the one hand, and self-reports of trait cooperativeness and empathy on the other. A coherent picture was obtained in women whose inhibitory control proficiency predicted higher scores on the Temperament and Character Inventory Cooperativeness and a higher Empathy Quotient. Individual differences in working memory did not predict self-reported empathy. In men, the association between SART performance and empathy was less clear: Good performance on the inhibitory task predicted lower scores on Cooperativeness and was unrelated to the Empathy Quotient. In both studies, women outperformed men on the SART. The results in women may reflect how individual differences in elemental neuro-cognitive operations such as inhibitory control influence more complex functions such as social cognition. (Contains 3 tables and 2 figures.)