Although adolescent and adult females have consistently been found to experience depression at twice the rate of males, the college population has represented a notable exception, with equal rates of depression reported for males and females. Using a cross-sectional design with equivalent measures, we explored the nature of these shifting population statistics by the following: (a) examining whether college females were reporting lower levels of depression, or college males were reporting higher levels of depression, relative to same-sex high school peers; and (b) exploring a number of relevant psychological and psychosocial/environmental variables that might explain these shifts. Replicating previous findings on the presence or absence of gender differences in depression in adolescent vs. college subjects, our data also indicated that this shift could be accounted for by lower levels of depression reported by college, relative to high school, females. Moreover, although psychological variables were the best overall predictors of females' depression levels, differences between high school and college females were best explained by psychosocial/environmental variables. Results are discussed in terms of the contextual features associated with the college environment that might protect women against depression and account for differential depression levels.