Biotechnologies already on the horizon will enable us to be smarter, have better memories, be stronger and quicker, have more stamina, live longer, be more resistant to diseases, and enjoy richer emotional lives. To some of us, these prospects are heartening; to others, they are dreadful. In Beyond Humanity, Allen E. Buchanan offers a powerful and controversial exploration of urgent ethical issues concerning human enhancement. He argues that there arepowerful reasons for us to embark on the enhancement enterprise, and no objections to enhancement that are sufficient to outweigh them.