The expression “human dignity” is used very widely today, but it is also used in a wide variety of ways. Is the notion irrevocably vague and vacuous, or can it indeed perform serious philosophical and moral work? Can and should talk of dignity be extended beyond the human to other living and even non-living beings or institutions? Regardless of the positions taken on these questions, it must be acknowledged that implicit opinions about human dignity are present in many areas of life, society and culture. To enquire about human dignity is nothing less than to think philosophically about what it means to be human. This is of fundamental importance in the 21st century as humanity grapples with the fast pace of technological change, the huge inequalities present in the world, and the question of our place and role in the ecology of our planet.