Billy Millwee, who oversees the state's giant Medicaid and Children's Health Insurance programs, will retire in August. 

Millwee has been a state employee for more than 20 years — 18 of them with Texas' Medicaid program, which at last count served more than 3.3 million poor or profoundly disabled Texans, the majority of them children. He has directed the Medicaid and CHIP programs, which account for nearly a quarter of the state's total budget, since early 2010. Before that he managed the Medicaid eligibility and claims system, Medicaid managed care and the state's medical transportation program, all while watching enrollment soar. 

"I can tell you that serving as the Texas Medicaid and CHIP director have been the highlight of my career," he wrote in a letter to senior staff over the weekend. "There has been no shortage of challenges, great opportunities, nor better people to work with." 

It's a complicated time for Medicaid. Whether the U.S. Supreme Court upholds federal health reform legislation will largely determine the future of the program, and how many more Texans will be added to the state's already staggering rolls. In 2011, facing a massive budget shortfall, lawmakers had to take the ax to Medicaid programs to balance the budget. They left $4.8 billion unfunded, which will have to be made up somewhere in the upcoming 2013 session — where finances are again looking slim.  

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Millwee said in his letter that he will work with Health and Human Services Executive Commissioner Tom Suehs to develop a transition plan "to ensure my departure is an orderly one."

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