When hearing the word "Paparazzi" most people will think about the dark side of photography. A Paparazzi is often pictured as a stalker who follows celebrities, invade their privacy and taking pictures of them by any means necessary without permission. There are so many controversial stories about paparazzi that raised a lot of concerns about this profession, mainly because these paparazzi’s often do illegal things and aggressive approaches just to get their shots, which sometimes could be dangerous to themselves or their targets. However, despite of all the controversies surrounding this profession, tabloids and many other medias still appreciate their work because the public actually still demand it.
Basically, paparazzi will hangout in public places waiting for a chance to take photographs of a public figure. In public areas, actually it's completely legal for a paparazzi to take any picture, but usually such pictures don't worth a lot of money. In order to make big bucks, the paparazzi needs to be in the right place at the right time to produce some interesting shots. So waiting around in the public place is just not efficient enough.
That's why most paparazzi’s are working like private detectives, they investigate their targets, try to find out where they are going and what they're planning to do, who they meet, etc. Usually they also have a network of informers that can help them keep tabs of their targets.
Paparazzi’s could be so creative in trying to get a good shot of their targets. Technically, in order to get a legal picture, the paparazzi must get the target to a public area, because it's illegal to take pictures in a private residence or business place. But when the target is in a private area, the paparazzi still can take the picture as long as he/she is standing on a public land.