This bulletin presents information on the youth detention population in Australia from June 2014 to June 2018. Among the 980 young people in detention on an average night in the June quarter 2018, most were male (90%), aged 10–17 (84%), unsentenced (60%), and Aboriginal or Torres Strait Islander (54%). Over the 4-year period, the number of young people in detention rose, though rates fluctuated across quarters.