Contemporary debates on free will are numerous and multifaceted. According to compatibilists, it is possible for an agent to be determined in all her choices and actions and still be free. Incompatibilists, on the other hand, think that the existence of free will is incompatible with the truth of determinism. There are also two dominant conceptions of the nature of free will. According to the first, it is primarily a function of being able to do otherwise than one in fact does. The second approach focuses on issues of sourcehood, holding that free will is primarily a function of an agent being the source of her actions in a particular way. This book guides the student through all these debates, demarcating the different conceptions of free will, exploring the relationships between them, and examining how they relate to the debate between compatibilists and incompatibilists. In the process, it addresses a number of other views, including revisionism and free will scepticism. This is the ideal introduction to the contemporary debates for students at all levels.