The investigation of sudden or unexplained death of children represents a unique medical and forensic area of study. Children are not simply small versions of adults. They have unique anatomic and functional characteristics that must be recognized and understood by the medical investigator. Further complicating this process is the fact that the anatomic structure, composition, and function of various organs and organ systems in the pediatric population change throughout the developmental stages of childhood. The disease processes, reactions to trauma, and risk factors for accidental death and homicide change from infancy through adolescence. There are many texts devoted to the medical investigation of child abuse in living children. And there are several excellent texts on general forensic pathology. There are outstanding reference texts on pediatric pathology that concentrate on the pathologic diagnosis of natural disease processes in living children. At present, there is no well known, thorough reference text devoted to the medicolegal investigation of sudden unexpected death in children. Further, there is no widely accepted text dealing with the changes in fatal diseases, risk factors of causes of sudden death, and responses to fatal trauma that occur as a child grows. We propose a text devoted to the medicolegal investigation of sudden and unexpected childhood death. We will organize the text based on chronological age. The text will begin with the newborn age, progress through infancy, toddlerhood, childhood, and conclude with adolescence. Through each major age group, individual chapters will focus on specific unique causes, topics, or organ systems. This text will be a unique contribution to the forensic science literature. This text will fill a niche that medicolegal death investigators are anxious to have provided. Potential purchasers of this text include forensic pathologists, medical examiner offices, pediatric pathologists, pediatric hospitals, anatomic pathologists, coroners, law enforcement investigators, pathology training programs, medical schools, child protection social workers and offices, colleges of social work, colleges of criminal justice administration, and colleges of forensic sciences.