MtheGM - As Peter says, Joni Mitchell's early albums through to the album "Blue" were absolutely classic, and "Blue" is a masterpiece. She was also, as he says, a great innovator.

In Joan Baez's case, well, she was just untouchable when she first appeared on the scene...she was the Queen...the Madonna...she was it. And everything (in female folksingers) that followed after for quite some time would be compared to Joan Baez. But she didn't write songs at all when she started out. She did write some poetry, but was under the impression she could not write songs. Bob Dylan advised her one day (over a coffee) that anyone could write songs. By the late 60s she was writing some songs. At first I would say they were...interesting...but a bit stilted. She hit her stride, however, in the mid-70s and began writing some very good material. The standout is the song "Diamonds and Rust", which I think is a masterpiece.

Now, in Buffy's case...she did actually do some trad songs on her early albums, but for the most part she was writing her own songs about personal viewpoints and/or social issues, and they were very good. I think Buffy Sainte-Marie is one of the finest songwriters, composers, and performers that I have ever seen.

As for Janis Joplin, I agree with Peter's remarks that she gave herself entirely over to the performance...yes...but I can barely stand to listen to how she sings, and I DO know someone who ruined her own voice and permanently damaged it by trying to sound just like Janis Joplin (God knows why anyone would do that...). One Joplin song I do thoroughly enjoy, though, is "Take a Piece of my Heart", backed by Big Brother and the Holding Company. That one was darned good.