[Foreward to the 26-page book of Joni's lyrics, published as a part of the Guardian's 'Great Lyricists' series]

I wrote a radio play a few years ago, setting it in 1973. Its 15-year old heroine worked in a library, wore long frocks, had long, straight hair, and was completely autobiographical. Here is a short scene:

A dulcimer or guitar is strummed rather badly.
LAURA (sings in high screechy manner, the song patterned on Joni Mitchell's A Case of You)
I could read a stack of you, David
A multi-volume set!

(She retunes a string, and makes matters slightly worse. She's making up the song as she goes along)
LAURA (cont'd, still singing)

You live in Stevenage
You took a Masters
Degree in Coventry!
You are so shy and lean
I even like the way you read Tolkien!
You're my introduction and my text
You are my dum-durn-dum index!
Oh I could read a stack of you, David
And my eyesight would never be vexed!
No, my eyesight would never be vexed!

No disrespect was intended by this, of course -except to my younger, earth-bound self. I was surprised recently to learn that Joni Mitchell's 1971 album Blue sold half a million copies; it made such an enormous impact on sensitive, long-haired, darkened bedroom people of my generation that I assumed it had actually been more. Personally, I learned all Joni's lyrics off by heart as each of the early albums came out -Ladies of the Canyon (1970), Blue, For the Roses (1972), Court and Spark (1974) -and yearned to be able to write the same sort of emotionally raw but musically sophisticated voice-of-experience songs, despite the obviously inconvenient fact that (to take just the example of A Case of You) I had personally never been involved in souls pouring into each other; there was absolutely no one in my blood like holy wine; I couldn't imagine what a cartoon coaster was; and to be perfectly frank, I was still at school. Might it have helped if I'd turned the lights on"? We will never know. But anyway, it's an unavoidable truth that, looking back, the only thing I had in common with the singer of A Case of You was that I could draw a map of Canada.

Joni Mitchell is generally admitted to be one of the most influential songwriters of the past 40 years; she is also said to be one of the most immodest, because she routinely compares herself with Picasso and Bob Dylan. I tend to think of her simply as a supremely driven artist worthy of complete admiration -whether restless in pursuit of herself, or in running away from herself, it hardly seems to matter, because the journey is the point.

Women in unhappy solo flight have always had an appeal for me, and I blame Joni Mitchell entirely. From her earliest album, Song to a Seagull (1968), she was always telling us she was leaving on the "1:15" (darn right), or pulling "into the Cactus Tree Motel /to shower off the dust"; or calling for this crazy bird to turn around (because she shouldn't have got on this flight tonight). She wished she had a river she could skate away on. She wanted the wind to carry her. She was a hitcher, "a prisoner of the white lines on the freeway". She was travelling in some vehicle, sitting in some cafe. One of her best-selling singles was Free Man in Paris (1974). This was one of her very rare songs about someone else, of course, but it was about someone who had clearly said something she wholeheartedly agreed with. "I was a free man in Paris / I felt unfettered and alive."

I know she irritates some people. Egocentric, introspective women, even when they are geniuses, are a bit of a challenge. Also, fair enough, some people never liked the shrieky bits, or the giggle at the end of Big Yellow Taxi. But when BBC4 showed an Old Grey Whistle Test session last year from around 1974, it was truly startling to see such sheer musicianship and compositional ambition embodied in a slim, beautiful young woman in a crocheted top, who looked like she might sing something about daddy taking her to the zoo tomorrow, zoo tomorrow, zoo tomorrow. What I now wish is that the lyrics in this booklet were not so familiar. How many times have I heard Joni sing Blue, with its first line, "Blue songs are like tattoos", and not stopped to think how deeply this song itself has got right under my skin"?