The relation between maternal alcohol consumption and infant attachment behavior at 1 year of age was investigated. Alcohol consumption was estimated by self-report questionnaires that were filled out by mothers over 30 years of age regarding the amount of alcohol they had consumed prior to, during, and following pregnancy. The attachment behavior of infants was observed using the Ainsworth “strange-situation” procedure. Infants were classified as secure (Group B); insecure-avoidant (Group A); or insecure-ambivalent/resistant (Group C). Additionally, a new classification of insecure-disorganized/disoriented (Group D), developed by , was used. The majority of infants of mothers who had consumed more alcohol were insecure in comparison with a minority of insecure infants of mothers who had been abstinent or light drinkers. The classification of infants as insecure-disorganized/disoriented helped to identify a large number of infants who were insecure in the group of heavy-drinking mothers.