From 2003:
I just saw the press preview of Wicked, a new Broadway musical based on the novel of the same name by Gregory Maguire. I brought with me a friend who is a huge Maguire fan, and who bristled visibly at every departure from the original. Not having read the novel, I wasn’t bothered by the differences, even after my friend told me how extensively the authors of the show had altered what Maguire wrote. But I knew how she felt. If you’re going to make a stage or screen adaptation of a familiar work of art, you really only have two viable alternatives: try to reproduce the original as closely as possible, or go your own way. Anything in between is doomed to failure….
Read the whole thing here.