This report is the 17th in a series that began in 1998. It provides statistics from BJS's Annual Survey of Jails in Indian Country on the demographic characteristics, most serious offense, and conviction status of the tribal inmate population, and it describes facility characteristics, including bed space and staffing. This report supports the mandate established by the Tribal Law and Order Act of 2010 that requires BJS to establish and implement a tribal data collection system, to support tribal participation in national records and information systems, and to annually report to Congress the data collected and analyzed in accordance with the act. The report indicates that a total of 84 jails in Indian country held an estimated 2,870 inmates at midyear 2018, up from 2,820 inmates in 2017 and from 1,775 inmates (held in 68 facilities) in 2000.Jails in Indian country were rated to hold an estimated maximum of 4,290 inmates at midyear 2018, up from 4,200 at midyear 2017. From midyear 2000 to midyear 2018, the overall rated capacity of jails in Indian country increased by 107 percent, and the midyear inmate population increased by 62 percent. Occupied bed space declined from 86 percent of rated capacity at midyear 2000 to 67 percent at midyear 2018.