This research bulletin includes reports of research in progress or recently completed from September 1971 through February 1972. Each entry includes information concerning the investigator, purpose, subjects, methods, duration, cooperating groups, and findings (if available). The reports are listed under several topical headings: (1) Long-Term Research, (2) Growth and Development, (3) Special Groups of Children, (4) The Child in the Family, (5) Socioeconomic and Cultural Factors, (6) Educational Factors and Services, (7) Social Services, and (8) Health Services. In addition to the reports on research, an extensive review paper entitled "The Vocal Behavior of Infants" is included. The paper presents a discussion of research methodology and data gathering strategies related to the descriptive characteristics of infant vocalizations, the learning theory approach to vocal behavior, conditioned vocal responses, conditioned response differentiation, reinforcer effectiveness, age and conditionality, and mother-infant interaction patterns. (SDH)