Abstract: This essay offers an account of the diverse range of rich insights Professor Finnis’s work offers for several perennial questions of constitutional theory: such as what valuable moral ends constitutional law serves, how best to approach the design of constitutional arrangements and institutions, and how to best approach constitutional interpretation. I proceed in four parts. The first two parts begin by looking at Finnis’s treatment of the purpose of law as a social practice and then, more specifically, the point or purpose of channeling political power through constitutional law. Having outlined the point or purpose of constitutional law and constitutional institutions, I then probe what Finnis has to say about que...