For most of the 20th century, in the West, at least, we believed that "Sleeping Beauty" was the one great 19th century classical ballet that hadn't changed very much. It's so tightly constructed (and so matches the score) that it hadn't been tampered with.

Well, like many things we all "know," this has turned out not to be quite true. For those interested in history, I'd suggest reading Doug Fullington's article about the recent reconstruction of "Sleeping Beauty" that's posted on Marc Haegeman's web site: http://users.skynet.be/ballet-lovers/Beauty1.html

There's also a lot of material on the ballet by Mel Johnson on this site:

http://www.balletalert.com/ballets/Petipa/...ty/sleeping.htm