Construct validity of the newly developed Preschool Assessment of Attachment (PAA) wasexamined in a sample of depressed and nondepressed mothers and their preschoolers, focusingon attachment related differences in children's general caregiving environments, maternalpsychosocial functioning, and child behavior during interactions with mother. Mothers of securechildren were more emotionally and verbally responsive to their children than were mothers ofinsecure children, and secure children were emotionally more positive to their mothers than wereinsecure children. Mothers of secure children also reported higher levels of social supports thandid mothers of insecure children. Finally, dyads with children who lacked unitary, coherentattachment strategies (i.e., anxious depressed, defended/coercive, and insecure other)showed the worst functioning in all domains relative to all other attachment groups. Similar butslightly less robust findings were obtained with socioeconomic variables statistically controlled.These results lend support to the PAA as a valid system for the conceptualization andmeasurement of quality of attachment among preschoolers. Future research applications with thePAA are discussed.