Ohio's jail system is composed of four primary classifications: full-service, minimum-security, five-day, and eight-hour jails. Data on the State's 255 jails address the size of the jail population, the legal status of jail inmates, the length of confinement, average per diem costs, jail incidents, and minimum jail standards. During 1998 Ohio's jails held an average daily population of 16,100 persons, an 11-percent increase over the previous year and a 34-percent increase since 1994. On average, Ohio jails confined 144 persons per 100,000 residents. Despite the marked increase in the average daily population, there was no statewide crowding problem; however, crowding continues to be a problem for full-service jails in urban areas throughout the State. Full-service jails showed the greatest amount of variation between sentenced and unsentenced inmates, with approximately 52 percent unsentenced, 46 percent sentenced, and 2 percent "other." Offenders held in the jails are staying for longer period of time on average, with the average stay in a full-service jail increasing to 23.77 days, an increase of almost 4 days from 1997. 7 figures and 4 tables