This article considers the neuroendocrine factors leading to systematic differences in trait verbal aggression (VA). Verbally aggressive people produce messages that attack the self-concept of another (D. A. Infante & C. J. Wigley, 1986). A neuroendocrine factor, prenatal androgen exposure (PNAE), was proposed as a possible predictor of VA. To explore this possibility, the relationship between the ratio between the length of the second digit and fourth digit (2D:4D), an indicator of PNAE, and VA was examined across 2 studies. Specifically, it was predicted that variance in PNAE would be correlated with variance in trait VA. Results from the 2 studies indicated that 2D:4D is correlated with VA as predicted, even with the influence of sex removed. © 2012 International Communication Association.