Attachment theory asserts that human beings are innately programmed to seek and form attachments with others. The assumption that the quality of early attachment relationships will be functionally related to subsequent attachment styles and competencies provides the theoretical basis for extending the theory of attachment to the study of adult personality and relationships. This review considers conceptual distinctions among the different measures of attachment and reviews and critiques the reliability and validity of scores on selected measures of adult attachment. The following instruments are considered: (1) Attachment Style Measure; (2) Adult Attachment Scale; (3) Attachment Interview; (4) Relationship Scales Questionnaire; (5) Measure of Insecure Attachment; (6) Inventory of Parent and Peer Attachment; (7) Parental Bonding Instrument; (8) Parental Attachment Questionnaire; (9) Bell Object Relations Inventory; (10) Attachment Style Questionnaire; and (11) Adult Attachment Interview. The analysis reveals that these measures each reflect different conceptions of adult attachment patterns and testing strategies. They differ in content domains assessed and in the specificity with which attachment representations are defined. Self-report measures may be more subject to defensive distortions, while interview-type measures may be more sensitive measures of adult attachment. (Contains 1 table and 36 references.) (Author/SLD)