In an essay in Sunday's Outlook section, Dartmouth ethics professor Ronald Green asks us to consider a neo-eugenic future of "designer babies," with parents assembling their children quite literally from genes selected from a catalogue. Distancing himself from the compulsory, state-sponsored eugenics that darkened the first half of the last century, Green instead celebrates the advent of a libertarian, consumer-driven eugenics motivated by the free play of human desire, technology and markets. He argues that this vision of the human future is desirable and very likely inevitable.