Accountable care organizations participating in the Medicare Shared Savings Program in 2014 or later may apply in July to participate in the ACO Investment Model, which offers prepaid shared savings to encourage ACOs to form in rural and underserved areas. Hospital participants must be critical access hospitals or inpatient prospective payment system hospitals with 100 or fewer beds. CMS also has accepted into the model six ACOs that joined the MSSP in 2012 and 2013, who will have a different payment structure under the model. For more information, see the CMS factsheet.