Despite medical technological advances, the major killers with which we must currently contend have remained essentially the same for the past few decades. Stroke, cancer, and heart disease together account for the vast majority of deaths in the United States. In addition, due to improved medical care, many Americans who would previously have died now survive these disorders, necessitating that they receive appropriate rehabilitation efforts. One result of our own medical advances is that we must now accept the high costs associated with providing quality care to individuals who develop one of these problems, and we must avail ourselves to assist of afflicted individuals. families Despite the relative stability of causes of death and disability, the health-care field is currently experiencing tremendous pressures, both from professionals with­ in the field, who desire more and better technology than is currently available, and from the public and other payers of health care (e.g., insurance companies), who seek an end to increasing health-care costs. These pressures, along with an increased emphasis on providing evidence of cost-effectiveness and quality assurance, are substantially changing the way that health-care professionals perform their jobs.