This volume consists of reports of individual studies and surveys of research work on mother-infant interactions. It is divided into two parts. The first section presents a wide range of studies on mother-infant relations as exhibited in the behavior of animals. The second part, concerning human behavior, includes studies on the natural history of crying, the effects of strange environment, the mental and emotional development of the thalidomide child, and several studies of babies' reactions to strangers. The work presented represents a pooling of several disciplines and demonstrates a variety of methods and theoretical backgrounds including psychoanalysis, psychology, ethology, and zoology. (JF)