In its latest briefing paper, the Manchester-based trust brings together Home Office statistics on how many young women are in custody in England and Wales, what provision is made for them, and issues they face.
According to the report, there were 117 15- to 17-year-old young women held in institutions in 2002.
Girls in Custody notes that the situation for young men and women differs in that men are found "age-appropriate places", while many young women are placed in adult institutions.
Mags Casey, spokesperson for the trust, said: "For the vast majority of young people, custody would appear to be an expensive and ineffective way to tackle crime."
www.youth-justice-trust.org.uk.