It was not so long ago that the dominant picture of Kant’s practical philosophy was formalistic, focusing almost exclusively on his Groundwork of the Metaphysics of Morals and Critique of Practical Reason. However, the overall picture of Kant’s wide-ranging philosophy has since been broadened and deepened. We now have a much more complete understanding of the range of Kant’s practical interests and of his contributions to areas as diverse as anthropology, pedagogy, and legal theory. What remains somewhat obscure, however, is how these different contributions hang together in the way that Kant suggests that they must. This book explores these different conceptions of humanity, morality, and legality in Kant as main ‘manifestations’ or ‘dimensions’ of practical normativity. These interrelated terms play a crucial role in highlighting different rational obligations, their source(s), and their applicability in the face of changing circumstances.