It is a shady business. Skulking around on street corners, clogging pavements, lurking in bushes, and goading cameras into people's faces. But the paparazzi say they have a job to do; a living to make.
I watched last Tuesday as the horde of photographers who set up camp outside Kate Middleton's Chelsea home waited to catch a 25th-birthday shot - or even better, a glimpse of a rumoured engagement ring. The frenzy evoked disturbing echoes of the worst days of Diana, Princess of Wales, who was eventually pursued to her death. I watched Ms Middleton's handling of her new status as the paparazzi's number one prize.
While there is derision from the public, the siege mentality of the paps means the antipathy is mutual. As far as they were concerned, Tuesday's scrum was a legitimate "doorstepping" opportunity on the birthday of a potential royal.
There was little glamour and scant excitement; long, cold pauses divide frenzied, jostling melees of snapping. And then there is hostility from Ms Middleton's west London neighbours: "You are disgusting. Leave people alone."
Another explained loudly to her child, hustling him past the pack to his school: "These people have nothing to do. They are bad." Waiting with photographers for hours with no sign of Miss Middleton, they offer a different perspective: "We don't want to do it but if we don't there will be others."
Earlier, as I arrived at 7am I was greeted with the indifference, silence and shrugs reserved for anyone outside the coterie. Not all those hoping for the killer shot were guns for hire. Newspapers and legitimate international news agencies such as the Associated Press were lined up.
Indeed, for the genuine paparazzo, Ms Middleton offers diminishing returns. Some publishers including News International, the owner of The Sun, News of the World and The Times last week banished pap shots of Kate from their pages. Hello! magazine followed suit and went as far as to inform Ms Middleton's solicitors Harbottle & Lewis of its noble intent.
Nevertheless, the snappers on the street still name her as their "most wanted". The celebrity photo trade is big business and the UK-based agency Big Pictures, which supplies magazines such as Heat, has a turnover of £3m.
Most of the photographers and their employers are reluctant to discuss their work, and none wanted to be quoted by name.
Nevertheless they are quick to point out that as anyone with a cameraphone and little regard for the Press Complaints Commission guidelines can get a celeb shot in the street, they are forced to compete. One well-known photographer asked: "Where do you think the best pictures come from? Some bloke with a cameraphone pictured the most viewed picture of Saddam's hanging."
A picture agency boss, speaking anonymously, said: "Do you think the paparazzi would exist if people were not willing to pay obscene amounts for their pictures? Hasn't technology made all of us paparazzi?" he asked.
While newspapers have pulled back, as have many agencies, there are still some operators who will continue to push the boundaries.
Since the death of Diana, the PCC has dealt with cases of harassment with a quiet word in the ear of an editor, but its director, Tim Toulmin, told The Independent on Sunday that the international market sometimes proved an irresistible lure to bend the rules.
"The pressure of the PCC might steer the British press to behave in a certain way. But an international market is guiding demand and supply."
TOP OF THE PAPS: WHO THEY ARE, HOW THEY WORK AND WHO THEY SNAP
Founder of Big Pictures, one of the UK's leading picture agencies and now an international concern. Specialises in celeb shots, particularly those with stars looking their worst, for the likes of Heat and Closer magazines.
Most famous for: the first shot of David Beckham and Rebecca Loos.
The UK's best-known celeb snapper, Fraser is often invited by stars themselves to capture those secluded beach shots. Represents French agency Eliot Press and was briefly executive director of Express Newspapers in exchange for exclusive use of his shots.
Most famous for: first picture of Diana and Dodi Fayed kissing.
Rome-based photographer who is affectionately known as the "King of the Paparazzi", but whose tangles with stars, including brawls with the likes of Marlon Brando, have led to 160 hospital visits and 11 broken ribs.
Most famous for: shots of stars such as Liz Taylor, Frank Sinatra and Mel Gibson.Reuse content