We are most pleased to present Volume 3 of Developmental-Behavioral Disorders: Selected Topics, designed to serve as a companion for standard reference textbooks that address cogent issues in developmental pedi atrics. Periodic publications such as Selected Topics and theme-related articles, as well as continuing education programs, attempt to supple ment in a timely fashion the rapidly changing knowledge base in developmental-behavioral pediatrics. These media are important as forums for enhancing the quality of clinical practice, teaching skills, and research activities. The need is critical for periodically disseminating and updating information about issues in developmental medicine, in as much as this field of study continues to expand at a meteoric pace. During the past several decades, developmental medicine has been recognized as a defined subspecialty in pediatrics. The spectrum of problems encompassed by this discipline is relatively broad and at times clinically overwhelming. The ultimate goal of preventing delays, disorders, and/or dysfunctions from becoming chronic handicapping conditions has, by volume per se, created clinical dilemmas for pediatric health care providers. There are numerous facets of providing efficient and effective care, which in the field of developmental-behavioral pediatrics are often exaggerated impediments to the delivery of services by pri mary health care specialists, e. g. , time, clinical skills, need for interdisciplinary management, medical-legal responsibilities, financial reim bursements. These issues, as well as clinical problems, are still very much part of the information base to be disseminated to concerned pro fessionals.