This newsletter theme issue contains contributions by parents, practitioners, researchers, administrators, and providers of technical assistance, which explore aspects of the complex process of developmental assessment of infants and young children. They describe what is helpful and what can be harmful in current assessment practice. They offer guidelines for assessing development of young children from diverse sociocultural backgrounds, implementing family-directed evaluation and assessment, assessing adaptive competence, and formulating a systematic developmentally-based approach to the diagnostic classification of mental health and developmental disorders of infancy and early childhood. Feature articles include: "Toward a New Vision for the Developmental Assessment of Infants and Young Children" (Stanley I. Greenspan and others); "Thoughts on the Assessment of Young Children Whose Sociocultural Background Is Unfamiliar to the Assessor" (Isaura Barrera); "New Visions for the Developmental Assessment of Infants and Young Children: A Parent's Perspective" (Susan Rocco); "Family-Directed Evaluation and Assessment under the Individuals with Disabilities Education Act (IDEA): Lessons Learned from Experiences of Programs and Parents" (Carol Berman and others); "Journey to a Desirable Future: A Values-Based Model of Infant and Toddler Assessment" (Lucy Jane Miller and Brian A. McNulty); "Assessment of Adaptive Competence" (G. Gordon Williamson); and "Diagnostic Classification of Mental Health and Developmental Disorders of Infancy and Early Childhood" (Stanley I. Greenspan and Serena Wieder). Annotations for 2 videotapes and 10 publications conclude the issue. (JDD)