Drug-related illnesses and complications cost the American health care system billions of dollars each year. Medical errors account for approximately 100,000 deaths each year, and drugs are the most common cause of medical errors in hospitals. Synthesizing research studies from seven nations, Preventing Medication Errors and Improving Drug Therapy Outcomes: A Management Systems Approach identifies pharmacists as a strategic resource in solving the problem of preventable adverse outcomes from drug therapy. It identifies and describes the preventable adverse outcomes of drug therapy, explores the safety, cost-effectiveness, and quality of medications use from a management systems perspective, and proposes systematic solutions.