Over the last thirty years, humanity has discovered thousands of planets outside of our solar system. The discovery of extraterrestrial life could be imminent. This book explains how such a discovery might impact Islamic theology. It is the foundational reference on the subject, comprising a variety of different insights from both Sunni and Shi'i positions, from different Muslim contexts, and with chapters that compare and contrast Islamic perspectives with Christianity. Together, they address some of our biggest questions through an Islamic lens: What makes humans unique in the cosmos? What are the ethics of dealing with other sentient beings? And how universal is salvation? Given the accelerating advances in exoplanet research and astrobiology, the book is at the frontier of science and Islamic thought. Contributors include a range of leading experts from Muslim theologians, scholars of comparative religion and philosophers, to historians, social scientists and natural scientists.