The demand for health care is growing as the nation ages and seeks to provide coverage for the millions of Americans who lack health insurance. At the same time, escalating costs have led to a variety of initiatives to make the delivery of health care more effective and efficient. The allied health workforce is critical to the success of these efforts. The IOM held a workshop May 9-10, 2011, to examine the current allied health care workforce and consider how it can contribute to improving health care access, quality, and effectiveness.