Who: Jonathan Blum, 44
Leaving: The CMS as of May 16. Blum was named Medicare director in March 2009, becoming the agency's first political appointee under President Barack Obama. Last year, he was promoted to principal deputy administrator of the CMS. During his tenure, the agency developed its Medicare accountable care organization program, implemented the star-rating bonus system for Medicare Advantage plans and for the first time released data on Medicare payments for more than 800,000 physicians.
