Mother-infant attachment was studied in 24 mother/impaired infant dyads. The infants, from 12 to 26 months chronological age, manifested primary neurological impairment or undiagnosed delay in gross and fine motor development. Measures of general development and degree of child impairment significantly differentiated "classifiability" of attachment in the Ainsworth scheme; thus, the most severely impaired infants were rated "not classifiable." For those infants who were fully classifiable (80\% of the sample), only 1 measure of general development or degree of impairment differentiated quality of attachment classification. Infants rated higher on a measure of social responsiveness were more likely to possess secure attachments than those receiving lower ratings on the measure.