Post-graduation, in the early Nineties, I was certain of two seemingly contradictory things. 1) I didn't want a proper job of any description just yet, thank you very much, and 2) I wanted - after four years of university plus two of playing guitar in a penniless indie band - to earn some money. Both lazy and avaricious, without even knowing it I was already an ideal candidate for a career in the music business.

Shortly afterwards I stumbled into a job in the marketing department of the now-defunct major label London Records. London specialised in bright, shiny pop music - Bananarama, East 17, All Saints, Fine Young Cannibals. It was the sort of label that favoured that week's chart position over long-term artist development.

The marketing meetings were an eye-opener. Records were “this useless, stinking piece of shit”. Artists were “clowns”, “losers” and “spastics”. Like many a bright-eyed newbie before me I was quickly, viciously, disabused of the notion that record companies loved music.

It also soon became apparent that, if you were lazy and avaricious enough, there was only one area of the music business to be in. The kind of area where you could reasonably expect to be handed a six-figure salary, a BMW and a bottomless expense account in return for rolling out of bed at noon. A&R - Artiste and Repertoire, to give the full handle - is responsible for finding and developing new talent.

The name is a genteel hangover from another era, reeking of civility and respect, of Ahmet Ertegun in a spun-silk suit leafing through some sheet music with Ray Charles. The reality was somewhat different: a generation of twentysomethings blasted to the gills on cocaine, tearing around the world trying not to lose their jobs by doing something crazy. Like actually signing a band.

Inevitably I bluffed and blustered my way in. In the autumn of 1995 I went to a party in a Mayfair nightclub. The entertainment was provided by an easy-listening orchestra called the Mike Flowers Pops. I thought no more about it until a few days later when Chris Evans played Flowers's version of Wonderwall on his Radio 1 show. I gave Mike a call. A few weeks later we (note - when an act is succeeding an A&R man will always use the inclusive pronoun. When they fail they become “they”) nearly scored the Christmas No1, shipping nearly half a million singles, and like that - bosh! - I was a major-label A&R man.

There is a Hunter S.Thompson quote that has become the music industry's Magna Carta: “The music industry is a cruel and shallow money-trench. A long plastic hallway where thieves and pimps run free and good men die like dogs. There is also a negative side.” It's appropriate enough given that the dominant emotions within A&R culture are fear and loathing: fear that you had - or were about to - signed the wrong thing. Loathing because one of your peers had just signed the right thing.

“No one knows anything,” runs the Oscar-winning screenwriter William Goldman's maxim about Hollywood. None of the executives responsible for choosing hit films has the slightest idea what will work and what won't: the effects-laden blockbuster stiffs while the quirky little film no one wanted to make cleans up. So it goes in A&R - the can't-miss band goes belly up on the first single and that strange little indie record sells by the truckload.

I quickly learnt a key fundamental for survival in meetings - say everything with absolute certainty and as though your life depended upon it. I saw a very senior industry figure (someone who, in all likelihood, has signed and developed music which you own) throw the first White Stripes record out of a fourth floor window with the words: “No one will ever - ever - be having this f***ing nonsense!”

I went one further. As the last chords of a mildy hot demo hung in the air I punctured the silence in the conference room with: “Is anyone really going to be having another bunch of sub-Radiohead drivel?” Thus did I terminate our company's interest in the emerging Coldplay.

As you've probably gathered, there was a problem with my A&R career. I was absolutely terrible at it. But then again, so was everyone else. You were a success if you could produce a profitable act every two or three years. Which meant picking the right act just once biennially out of thousands of demos and hundreds of gigs. Of course virtually no one manages this. In a neat twist on “the unspeakable in pursuit of the uneatable”, the Wildean epithet about the foxhunting English upper classes, here was the unbelievable in pursuit of the unlistenable.

And pursue we did, jetting off every other month to some exotic location for a “convention”; a scarcely credible four-day holocaust of drugs and expense-account abuse. Miami for the Winter Music Conference, Cannes for MIDEM, Cologne for Pop Komm, New York for CMJ, Texas for South by South West: hundreds of A&R men spending hundreds of thousands of pounds on flights and entertainment. In a good year these conventions might produce one signing of note.

Of course, spending your twenties flying around the world on a diet of vodka and cocaine while being wildly overpaid does not make for reasonable, well-adjusted people. Arrogant? At a Janet Jackson party in the penthouse of the Chrysler Building I casually tossed my coat to Benny Medina, thinking he was a bouncer. Medina probably had better things to do: he was managing Jennifer Lopez and Mariah Carey at the time.

How were these levels of squander and buffoonery sustainable? Thanks to our good friend the compact disc. Today you can walk into Asda or Tesco and pick up an LP for seven or eight quid. Back in the mid- to late nineties a new release routinely cost £12 to £15 - nearly £30 in today's money. Factor in manufacturing costs of a few pence per unit and a royalty rate to the artist of about a quid and you're have a profit margin to make Third World sweatshop owners wince.

It seemed that the artificially inflated good times would roll for ever. Britpop lurched towards its swollen apogee. I remember standing in the corporate hospitality box at Oasis's Maine Road show in the spring of 1996, being entertained by jugglers and fire eaters, a glass of cold champagne in one hand. Far below, tens of thousands of tolers (industry shorthand for the lumpen proletariat who buy the product) gleefully smashed up Moss Side. I was thinking, “And when Alexander saw the breadth of his domain” ... or, more likely, “Where's the dealer?”

But, of course, elsewhere, the meter was running. By the time the new millennium was dawning I had an infant son I barely knew and a karma balance so overdrawn I would need to help several old ladies across the road every day for the remainder of many lifetimes to get it anywhere near the black.

A few years later (I was never any good at leaving a party early) I finally left the music industry for good. I became a novelist and decided to use my experiences, not to satirise the music industry so much as to blowtorch it. As the resultant book has begun to do the rounds I've re-established contact with a few people from my time in the business and I keep hearing the same things again and again: “It's tough out there ... redundancies all over ...”

The late Nineties are increasingly starting to resemble a glorious last hurrah for the music industry, a spangled fall-of-Rome era. The sales of CDs have declined year-on-year since 2000. Profit margins have been decimated. Bands give their music away free with newspapers to drive up ticket sales for their profitable live shows - a complete reversal of the time where an act lost money on the road in order to drive CD sales.

As an industry acquaintance put it recently, A&R men “used to go and see their band playing at Wembley and think: ‘I'm the king!' Now they are thinking: ‘I'm the only guy not making any money out of this!'”

Somehow I doubt we'll be holding a telethon any time soon ...

John Niven's novel Kill Your Friends is published by William Heinemann. He will be reading from the book at the Pineapple, Kentish Town, London NW5 (020-7284 4631), on Feb 20

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