Most discussions of Kantian dignity focus only upon what we might call “vertical dignity”, that is, our human dignity insofar as we somehow rise above animal nature and identify with our higher faculty of reason. In this paper, I instead explore Kant’s typically ignored account of “horizontal dignity”, that is, our human dignity insofar as we exist in concrete social relationships with other people. I offer detailed accounts both of (a) Kant’s negative view of “public heteronomy” in which we find ourselves dominated, not now by our own natural inclinations, but, ala Rousseau, by what Kant sees as the social “passions” of other people, and (b) Kant’s positive view of “social dignity”, where I discuss the social and political conditions required for it and how to realize such dignity via engaging in a “public use of reason” with other persons at both the interpersonal and societal level.