In the last decade, pharmacoepidemiology has emerged as an important field to study the use/effects of drugs in large populations in real life, allowing for improved benefits and effectiveness of drugs as well as a decline in drug-related risks. The correct assessment, reporting, monitoring, and prevention of adverse events in drugs' development, as well as therapy and post-market surveillance, is essential to improve clinical therapies and health outcomes. This book provides a comprehensive and unique overview of the relevance, new insights, and recent findings of pharmacoepidemiology and drug safety in public health.