This book attempts to explain what pharmacoepidemiology is, how pharmacoepidemiology studies are conducted, andhow to interpret pharmacoepidemiology findings. In Chapters 1 to 6, we explain the importance of pharmacoepidemiology, basic terminology used in pharmacoepidemiology research, and the data sources, study designs, and statistical analysesoften employed in pharmacoepidemiology research. Chapter 7 provides examples of evaluating a pharmacoepidemiologystudy. Two chapters provide detailed descriptions of the use of pharmacoepidemiology to understand medicationutilization (Chapter 8) and medication safety issues (Chapter 9). The final chapter discusses the perspective of the FDA onmedication safety, the importance of health care professionals to the process of improving medication safety, and the waysin which pharmacoepidemiology will be a key component of future medication safety initiatives. After reading the book, thereader should have a better understanding of how to evaluate the associations between medication utilization andoutcomes.