Research programs of the human learning and behavior branch of the National Institute of Child Health and Human Development (NICHHD) are described in five sections of this document. The specific programs conducted in the areas of learning and cognitive development, development of communicative abilities, biological bases of behavioral development, social and affective development, and health-related behaviors are reported in brief summaries which provide statements about research needs and problems under consideration, indicating various approaches researchers have taken in addressing the problems. A brief overview of the NICHHD's research centers and the learning and behavior branch precedes the program descriptions. In conclusion, future research emphases are recounted. Related materials are appended, including breakdowns of funding by projects in the behavioral sciences for Fiscal year 1979 (FY79), by primary disciplines (FY79), by program category (FY77-79), and by number of trainees and fellows (FY77-79). (RH)