This research examines the effects of early maternal employment on the cognitive ability of 2,040 4- to 6-year-old children drawn from the National Longitudinal Survey of Youth. Some scholars have hypothesized that it is the “most advantaged” of society's children who are disadvantaged or negatively affected by early maternal employment. If this hypothesis is true, the findings should be that advantages such as high levels of cognitive stimulation in the home or household income do not affect cognitive ability as strongly for children of mothers who were employed during early childhood as they do for children whose mothers were not employed. Of 24 possible interaction effects that would confirm this hypothesis, only one is statistically significant (and the nature of that interaction is not completely consistent with the hypothesis). In terms of effects on cognitive outcomes, the most advantaged children are not disproportionately disadvantaged by early maternal employment.