Attempts to assess maternal and neonatal behavior and subsequent mother-infant interactions as potential determinants of the quality of attachment between mothers and their infants provide the focus of this paper. Several instruments and procedures that focused on (1) maternal and infant characteristics, (2) mother-infant interaction, and (3) life stress, were used to collect data from 212 high risk pairs of mothers and infants. The collection of data began during the prenatal period and continued through the infant's first year of life. Attachment was assessed when the babies were 12 months of age. Using the Strange Situation Procedure researchers classified infants as anxious/avodiant (Group A), securely attached (Group B), or anxious/resistant (Group C). Overall group differences among the three attachment groups were tested by a one-way ANOVA and the Student-Newman-Keuls was used for post hoc comparisons. Results indicate that maternal, neonatal, and interactive factors contribute to the development of qualitatively different attachment relationships. Anxious/resistant infants appear to develop more slowly than others. Mothers of anxious/avodiant infants tend to be tense, irritable, disinterested in their babies, and react negatively to motherhood. Securely attached infants tend to have mothers who are sensitive to their needs and who encourage reciprocity. While male infants tend to be more vulnerable to caretaking differences, female infants may be more vulnerable to stressful life events than males are. (Author/RH)