The Housing First approach used by Pathways to Housing, Inc., was used to enhance residential independence and treatment retention of homeless, seriously mentally ill methadone patients. The Keeping Home project first secured scattered-site apartments and assertive community treatment services and then addressed patients' service needs. Three years post-implementation, methadone treatment retention for 31 Keeping Home patients versus 30 comparison participants (drawn from an administrative database) was 51.6% vs. 20% (p < .02); apartment/independent housing retention was 67.7% vs. 3% or 13% (both p's < .01). Although results firmly support Keeping Home, future research needs to address study's possible database limitations.