Riojas has a demanding job, pulling double duty since being named acting chief of staff in April 2013. In his twin roles, he is charged with preparing for worst-case scenarios as well as synchronizing the efforts of the VA's vast workforce—more than 300,000 employees. Sometimes, Riojas says, these daunting tasks can distract him from his core mission: Giving back to those who gave him so much. "I think the most challenging part for me lies in always keeping what matters most—the veterans—foremost in my mind," he says. Indeed, for Riojas, 58, the "most rewarding" aspect of his job is taking care of those who took care of him—the veterans who trained him as a cadet at West Point, mentored him as a young second lieutenant leading combat missions in the Middle East, and molded him into a career Army officer. "I feel honored and privileged to have the opportunity to work on their behalf to now make their lives better," Riojas says. Originally from Kansas City, Mo., he enrolled at West Point out of high school, and served more than 30 years in the armed forces. After leaving the military, he was vice president for strategic initiatives at the University of Texas (El Paso) while concurrently serving on several public-sector boards and committees. But when the VA came calling in 2009, Riojas knew where he was needed. "I can obviously never fully repay the debt I owe them," he says of his fellow veterans.