President Barack Obama named two women this week to lead his effort to overhaul the nation's healthcare system. One of them, Gov. Kathleen Sebelius of Kansas, began preparing for confirmation hearings. But the other woman, Nancy-Ann DeParle, can begin work right away, without outside review of her abilities or opinions. That is because DeParle holds the newly created post of "health czar"—one of several new "czar" positions that are within the White House and require no Senate review. Now, with the number of czars growing, some lawmakers and outside experts fear that Obama is concentrating too much policymaking and power within the White House—and also setting up the potential for conflict among his many advisers.