Changing sex. Not simple, not well understood, not consistently regulated, but here to stay and getting complicated. One Canadian clinic is carrying out 250 sex reassignments per year.

Women and men of all ages believe that identity is not as simple as what kind of genitalia they happen to be born with. In order to find their true identity, they're prepared to undergo major surgery-which can cost tens of thousands of dollars, and is most often irreversible.