ContributorsPrefaceI. Issues of Research Strategy Can the Longitudinal Method Be Applied to Psychological Studies of Human Development? The Place of Longitudinal Methods in the Study of Development Exploratory Studies in Cognitive Development An Analysis of Methodological Barriers to Cognitive Assessment of Preschool Children The Taxonomy of Tasks The Critical Need for Methodological Consistency in Field and Laboratory Studies Psychological Studies on Twins: a Test-Analytical ApproachII. Biological Determinants of Development Genetic Variations on the Hominid Theme: Individual, Sex, and Ethnic Differences Development in Psychological Twin Research Variability of Intraclass Correlations in Twins On Status and Developmental Rate in Certain Human Characteristics: Preliminary Findings from a Follow-up Study of Twins and Unrelated Coevals Sexual Dimorphism: Its Significance in Human Development The Relation between Genetic Factors and Social Influence in Psychosexual Development during Adolescence Socio-Biological Influences on Children's Development Genetic and Social Factors in the Development of the Handicapped Normal ChildIII. Cultural and Societal Factors in Development Social Class and Human Development The Changing Individual in the Changing Society Culture and Development Realism of Self-Appraisal and School Achievement in Eight Countries Cross-Cultural Design in the Study of Structural Aspects of Development during Middle and Later Adulthood Some Socio-Demographic Correlates of Measured Intelligence in IranIV. The Concepts of Deprivation and Enrichment Enrichment and Deprivation: towards a Conceptual and Empirical Differentiation of the Early Environment Personalities of Deprived Children Deficiency Conditions of Stimulation and the Reversal of Their Effects via Enrichment Problems and Issues in the Study of Deprivation and Enrichment Intellectual Development and Stimulation in Early Childhood: an Investigation of the Irreversibility of the Learning Process Ontogenetic Contributions to Aggressive Behavior The Later Outcome of Early Care by the Mother and Substitute Daily Regimes Educational Television Programs for Young Children: a Matter of Concern for Those Involved in Early EducationV. The Infant: Selected Studies A Twin Study of Infant-Mother Interaction Electronic Recording of Behavioral Interaction Information Processing and Human Newborn Heart Rate Response Some Social Responses of Infants and Mothers in Three Israeli Child-Rearing Environments: Bedouin, Kibbutz, and Urban Middle-Class Mothers and Fathers, Girls and Boys: Attachment Behavior in the One-Year-Old Individual Differences in Play Behavior: a Mathematical Analysis Patterns of Vocal and Gestural Imitation in Infants Variations in Perceptual Responses of Infants and Their Correlates in Level of Intelligence and Emotional Behavior in Later Childhood Detection of Cross-Stage Relations between Transition Periods in which the Form of Behavior Differs Markedly: Approaches Used and Findings from a Longitudinal Study of the Newborn and Preschool PeriodsVI.