The opening chapter presents definitions of juvenile, delinquent child, felony, misdemeanor, reasonable suspicion, probable cause, frisk, and child in need of services (CHINS). The discussion of a stop, threshold inquiry, and frisk considers when and how to make a stop and threshold inquiry, and consent. The chapter on questioning a juvenile encompasses questioning a stopped juvenile, interviewing a juvenile witness or informant, and interrogating a juvenile suspect. Juvenile rights relevant to questioning are also considered. Topics considered under warrantless searches include consent searches, vehicle stop and frisk, plain view searches, searches incident to arrest, and exigent circumstances. Instruction on arrest procedures distinguishes between an arrest and a stop and discusses probable cause for an arrest, arrest with and without a warrant, arrest under varying circumstances, and police procedures following arrest. Following guidance on procedures for detention, protective custody, and police operations on school grounds, the arrest and detention of CHINS are examined. The concluding chapter focuses on identifying and reporting suspected child abuse or neglect. The appendix contains an overview of the processing of delinquency cases in Massachusetts. Sixty-six notes are provided.