The first few years of life are a time of unparalleled physical, intellectual, and emotional development. They can also be a time of neglect and abuse for this is the period when children are most likely to suffer mistreatment by their parents, and most likely to be placed in foster care. Today most children entering the child welfare system are very young and in most large states, infants are the largest group of children entering foster care each year. Social service systems are typically not designed for very young children, and as a result fail to serve their special needs. This shortcoming is significant because protecting very young children from physical harm is not enough; they must also be protected from developmental harm. This work offers an overview of child welfare systems. It examines child abuse reporting patterns and discusses placement in foster care, reunification, and adoption. It also looks at public child welfare practice, and features examples of the children and families served by this system.