When a child or juvenile in Thailand is alleged to have committed an act against the law, the case is opened and investigated by an inquiry police officer, as required by ordinary criminal cases, but the processing of a juvenile offender is more informal and lenient. Formal arrests are made only when flagrant offenses are alleged. Juveniles may be detained during an investigation. The initial inquiry must be completed within 24 hours. Observation and protection centers prepare a social investigation report, conduct physical and mental examination, and prepare an observation report. If the public prosecutor decides to prosecute a case, a charge must be entered in juvenile court within 30 days from the time the juvenile was detained. Criminal proceedings for juveniles charged with an offense are the same as in an adult criminal court, except where juvenile and family court procedure provides otherwise. The empirical data address selected offenses committed by juveniles from 1988-92; statistics on psychological diagnoses, 1990-92; the residence areas of juvenile offenders, 1992; the recommendation on causation of an offense, 1992; and recidivist rates, percentage, and sex of offenders, 1992. The treatment program of a new juvenile training facility scheduled to open in 1995 is described. 5 tables and 36 references