Shy and inhibited behavior in infancy is associated with increased risk for clinical levels of anxiety later in life. Although both genetic and environmental factors are associated with anxiety, little empirical work has addressed how developing regulatory abilities may exacerbate or mitigate risk. The current study was aimed at addressing this gap in research by investigating an early-emerging regulatory behavior, attention control, as a moderator of genetic and environmental risk for anxiety. Participants included 9-month-old adopted infants, their birth mothers, and their adoptive parents (n = 361). Structured interviews were used to obtain a lifetime diagnosis of birth mother social phobia. Adoptive parents completed self-report measures of anxiety symptoms. Infant shyness and attention control were coded during a stranger interaction and a barrier task, respectively. Neither adoptive parent nor birth parent anxiety were directly associated with shyness/inhibition. These risk factors were, however, moderated by attention control in infants whose birth mothers met DSM-IV criteria for social phobia. When these infants were raised by adoptive parents with high self-reported anxiety, greater attention control was associated with greater shyness/inhibition. In contrast, when raised by adoptive parents with low self-reported anxiety, greater attention control was associated with less shyness/inhibition.