The investigation of child abuse is a critical and sensitive issue that affects the safety and well-being of children nationwide. It is estimated that law enforcement agencies in the United States investigate more than 3.3 million cases of child maltreatment each year and that as many as 2,000 children die as a result of this maltreatment. Law enforcement personnel are responsible for protecting children and often have the difficult task of determining if a child's injury is accidental or deliberately inflicted. Careful investigation is required to determine whether a child's injuries are accidental or intentional. This guide, first developed in 1996, provides information about the many indicators of child maltreatment and abuse to help first responders and investigators differentiate between physical abuse and accidental injury. Over the years, advancements in medicine have helped further distinguish between accidental and abusive injuries. This fourth edition of the guide reflects the most current literature on how to distinguish between types of injuries and includes the questions that investigating officers must ask.