"For Good" from Wicked - Stephen Schwartz

Perhaps Stephen Schwartz' most well-known work (at least these days - Godspell was 1971), Wicked is one of my favorite musicals.  One of those that I can quote all of the music, and most of the book (having seen it three times :)  This song is one of the concluding numbers, when the "good" and "wicked" witches of Oz are saying farewell.