Teacher certification trends in the United States since World War II paint a complicated picture of powerful interests at different levels making demands and trying to institute disparate reforms. These patterns have varied over time, often because of teacher supply and demand. The federal government initiated its involvement when education professionals' competence came under attack in the years following the launch of Sputnik. The tensions over the size and scope of state and federal control that characterize many areas of American policy are crucial in education. The current policy environment in the United States involves several seemingly contradictory components and adversarial actors. As the United States attempts to reform its education system in response to the ever-increasing demands of participation in the global economy, control of teacher preparation and certification will continue to have to respond to multiple stakeholders.