Many of the challenges that people experiencing homelessness, living in PSH, and other people with extremely low incomes had with enrolling in Medicaid were lessened after full implementation of the Affordable Care Act in 2014. On January 1, 2014, individuals with incomes lower than 133 percent of the federal poverty level, including those who are or were experiencing homelessness, became eligible for Medicaid for the first time on the basis of income in 25 states and the District of Columbia. About 64 percent of people experiencing homelessness reside in the states currently going forward with expanded eligibility (HUD 2012, p.5), increasing the likelihood that people experiencing homelessness or living in PSH will be able to access the services they need. A high percentage of people experiencing chronic homelessness have a serious mental illness, usually coupled with co-occurring behavioral and physical health conditions. Alternative Benefit Plans, in which they are likely to be enrolled, include behavioral health services as part of the essential benefits required by the Affordable Care Act, which will make these services available for the first time to many of the new beneficiaries. Further, streamlining of eligibility determination and recertification should make enrollment easier and greatly simplify maintaining eligibility, which should reduce the problem of enrollment churning. Reaching and engaging people experiencing homelessness or living in PSH and keeping them enrolled will always be challenging, but new options for covering the costs of care coordination under the Affordable Care Act, plus increased provider experience over time, should begin to address these issues. Given the importance of Medicaid coverage for people with complex health and behavioral health conditions, the changes evolving under the Affordable Care Act show the promise of bringing more people into care, providing more appropriate and coordinated care, and helping them remain in care.