We test whether infants living with employed, co-resident parents where at least one parent works a non-standard work shift exhibit significantly more behavior problems than children whose parents both work traditional day shifts. We use a sample of infants living with employed, co-resident parents and two waves of data from the Early Childhood Longitudinal Survey, Birth Cohort (ECLSB) to test whether infants' scores on the Infant-Toddler Symptom Checklist (ITSC) at the second wave (average age of 24.3 months) is affected by parents' shift work at the baseline (average age 10.3 months). Infants with at least one parent who works nonstandard hours have significantly more behavior problems than do infants with parents who both work regular day shifts. This relationship is partly accounted for by shift work's negative association with father-child interaction, marital quality, the frequency of shared family dinners, and parental health, including paternal depression. The results also indicate that shift work has larger effects on children's behavior when mothers, rather than fathers, work nonstandard shifts, and when mothers' day shifts regularly oppose fathers' evenings/night shifts. Policy should focus on giving individuals more choice in their work shift as well as more flexibility in when they start and stop working for the day. Given the importance of mediating factors, we should also focus on ameliorating the negative impacts of shift work when they do arise. This includes addressing issues of employee health and stress, and relationship conflict within couples where one or both partners work a non-standard shift.