Launched in the 1990s by the Annie E. Casey Foundation as a five-site demonstration project, the Juvenile Detention Alternatives Initiative (JDAI) has steadily swept the country in recent years and is on track to become the standard of practice for how local justice systems nationwide handle the critical front end of the juvenile court process. This report documents JDAI's recent progress both in reforming juvenile detention practices nationwide and also in contributing to the larger movement for more comprehensive reforms in juvenile justice. This report discusses the following: (1) why juvenile detention reform matters; (2) how JDAI works; (3) how widely the JDAI model is being replicated nationwide; (4) the participating sites that have been achieved through detention reform; (5) how detention reform has stimulated or supported broader changes in juvenile justice; and (6) the future challenges for JDAI. (Contains 18 figures and 15 endnotes.)