This study assessed the association between aspects of mother's employment and security of infant-mother attachment, in combination with proximal (maternal sensitivity) and distal (demographic, maternal, child, child-care) factors. Participants were 145 Australian mothers and their firstborn children. Attachment security was assessed with the Strange Situation at 12 months. Results showed that mothers' prenatal attitudes to work and timing of the return to work made significant, independent contributions to attachment outcomes over and above the effects of proximal and distal predictors. Mothers who expressed more commitment to work and less anxiety about using nonfamily child care, and who returned to work earlier, were more likely to have secure infants. These findings are considered in relation to contemporary expectations about mothers' participation in paid work and other predictors of secure attachment.