Free will is an essential problem in human knowledge that investigates the relationships between all creatures, including human beings, with each other, nature, and ecosystem. The immense impacts of free will on science, law, and ethics and, as a result, on everyday life of humans are undeniable. This is the reason behind almost two centuries of intense research by well-known researchers on this historic problem in the Western world. This book, based on a constructive modeling of the problem, provides its solution and analyzes its applications in science, law, and ethics.