I WAS 12 when I got my first camera: it was an Olympus. I'd always been interested in newspapers because my father was a foreign correspondent, so I started taking pictures of local events, which I sold to local newspapers. I took pictures of anything - it could be a woman chucking water over her doorstep, a celebrity event, riots, demonstrations - we lived in London and I went to everything.

I got both my press card and my first scoop in a national paper when I was 15. I was watching the Miss World competition on television, and the contenders were wearing fur coats. Suddenly, there was a noise on TV and I could tell something was up. So I ran out of the front door, jumped into a cab and belted down the road to where it was happening. When I got there I saw the police dragging these anti-fur protesters by the hair: I was the only person to get photos of it. The picture editor of the Sun gave me a wry smile when I went in to give him the pictures - I was little more than a schoolboy really. I remember the headline in the paper: 'Fur flies at Miss World.'

I'm 27 now and I work for all the tabloids, broadsheets and the international press. Although I've covered all types of hard news, I've come to the conclusion that there is nothing more fascinating than a candid picture of a well-known personality. I concentrate on celebrities and royalty.

This week I've photographed Thea, the widow of the former New Zealand prime minister, Sir Robert Muldoon. That was a very easy one; it only took half a day. I photographed her on the Tube and out shopping. I used a combination of telephoto lenses and four discreet wide-angled cameras. I was wearing a suit, and the cameras fit under a jacket so she didn't know I was photographing her.

I don't feel bad about something like that: Muldoon's tenure as prime minister was steeped in scandal. I think it was legitimate to photograph her. It's in the public's interest.

I work very hard when there is work around and when informants are providing me with stories, but then I take time off. This usually works out as one month on, and two or three weeks off. I don't like working with anybody else. I had a partner at one point, which is nice if you're doing stakeout - it's a solitary existence and it's nice to have company. I work with my wife now; she's a writer for various tabloids and we hunt things out together.

I've always needed excitement. I've always wanted to get the picture that nobody else got. Although I get paid a lot for the work I do, I don't do it for the money: I do it for the precious moments every year when the adrenalin rush is massive. In my kind of work, photography counts for only 10 per cent; 90 per cent of it is a combination of contacts, your personality, perserverance, patience and very careful planning. I'm always trying to think ahead: I have the first editions of the papers brought round to me at night so I can judge what the agenda will be the next day and what people will be after. It's a combination of being proactive and reactive.

My rule of thumb is that I will photograph somebody in a public place - by that I mean a beach, shopping on a street or in Battersea Park. What I will not do is photograph people when they're in hospital. I do not shoot people when they're in mourning. And I do not break into, or take pictures on private property. If they're by a pool in the Sheraton Hotel in Bangkok, I've got as much right as they have to be there, and to take a picture. I'm not going to go into their room, though.

I've always found it difficult to feel sorry for the Princess of Wales. She's been like a moth to a candle: she got too close to the press. She loved the adulation and being in the spotlight.

Then when it started to turn sour she tried to do a Greta Garbo. But it doesn't work like that. It would clearly have been in pretty bad taste for the tabloids to have bought the topless pictures. But then, none of them ever would have.

There is always this image of photographers as people in dirty raincoats with a foot jammed in the door, shoving a camera in somebody's face. That's complete rubbish. It's not like that. It was never like that. In my opinion, the tabloid papers are a breath of fresh air. More than half the British public reads them. That's more people than voted for any political party at the last election. That's what I'd call a consensus.

Interview by Catherine Milner