Through the Advance Payment Accountable Care Organization (ACO) initiative, CMS is testing the extent to which pre-paying a portion of future shared saving could increase participation in CMS’s Medicare Shared Savings Program (MSSP). While CMS previously announced that applications would only be accepted for April 1, 2012 and July 1, 2012 start dates, CMS now plans accept applications beginning August 1, 2012 for an additional round of Advance Payment ACOs that would begin on January 1, 2013.