This study concludes that even under worst-case assumptions, there are sufficient county institutional beds to house the entire DJF population and still have 200 to 1,000 empty beds remaining. There is more than sufficient available bed space in the 29 largest counties alone to absorb the current DJF population, virtually negating the need for additional State or county facilities. County per capita ward costs are substantially less than DJF per capita ward costs. Closing DJF facilities entirely would entail substantial State savings. The county costs will still be lower than the current State costs even with an increase in the per capita county costs resulting from the population of older, more serious offenders. The success of transferring all remaining juvenile justice functions to the counties depends on the State reallocating a portion of the DJF's budget to county probation departments in order to ensure they have sufficient resources to implement needed changes. Data for this analysis was obtained from the California Department of Corrections and Rehabilitation, Division of Juvenile Justice (statistics on juveniles in DJF and adult prisons); the Corrections Standards Authority (statistics on juveniles in county detention); Criminal Justice Statistics Center (statistics on juvenile crime by offense, year, and county); and Department of Finance (juvenile populations by year and county). Details of the data analysis are provided. 7 figures, 4 tables, and 26 references