This report is a portion of a study of attachment behavior: behavior promoting contact and/or proximity of an infant to his mother figure. This report deals specifically with crying, response to brief everyday separations from the mother and to her return, and behavior relevant to physical contact with her. The subjects, 26 infant-mother pairs from white, middle class families, were visited at home once every three weeks from 3 to 54 weeks, each visit lasting approximately four hours. From the observer's detailed notes, a narrative record was made of infant behavior and mother-infant interaction. The findings reported in quarter-year sets illustrate developmental trends, individual differences in the behavior of both mother and infant, and the relationship between maternal and infant behavior. The researchers conclude that (1) there are important qualitative differences in infant-mother attachment relationships; (2) no single criterion of attachment can serve as an adequate basis in all cases for determining the presence of infant attachment; (3) there is no present basis for assessing strength of attachment; and (4) mother-infant interaction seems to be linked to attachment behaviors and the quality of the attachment relationship. More than one-fourth of this document consists of references, footnotes, and tables. (Author/AJ)