This book explores the “whats,” “whys,” and “hows” of petitionary prayer. Millions of people every single day ask God or some other supernatural being to make some outcome or event happen, whether it be to keep their children safe during a road trip, to give them the willpower to avoid succumbing to the temptation of alcohol, or to help them find a job. The chapters in this volume draw on 130 in-depth interviews conducted in the United States, including non-Christian believers. The author provides extensive documentation and analyses of believers’ experiences and beliefs regarding petitionary prayer. He explores what outcomes believers feel they can legitimately seek through petitionary prayer, how people use petitionary prayer to persuade supernatural beings to make outcomes and events happen, why they believe petitionary prayer is actually effective, and why they believe their prayers went “unanswered.” Studying prayer in general and petitionary prayer in particular is an important part of describing and understanding people’s religious lives. The book will be of interest to scholars and students of religious studies, the sociology of religion, the psychology of religion, social psychology, and symbolic interactionism.