Wish I knew what this type of fish is called.
(Canon 7D + 50mm f/1.4 @ f/1.8, 1/200 sec, ISO 500)
Looks like a triggerfish of some kind.
I don't think it is a triggerfish...
Facial markings look like a Maori Wrasse (or Humphead wrasse/napoleon wrasse/napoleon maori wrasse - or any combination of these

)
I can't see a prominent hump and this looks a lot smaller than the typical adult maori wrasse... perhaps a juvenile one? Or I could be completely wrong and it may be a triggerfish - I haven't looked at fish ID books in a while.
Where did you see the fish? (And very nice photo by the way)