This study investigated low-income mothers' daily nighttime and weekend work and family outcomes. Sixty-one mothers of preschool-aged children reported daily on work hours, mood, mother-child interaction, and child behavior for two weeks (N = 724 person-days). Although nighttime and weekend work are both nonstandard schedules, results showed adverse associations of working nighttime hours on family outcomes--more negative mood and mother-child interactions; less positive child behavior--but no relationship between weekend work and family outcomes. (Contains 3 tables.)