Following the killing of Christchurch woman Renee Duckmanton, the New Zealand Prostitutes' Collective (NZPC) is stepping up efforts to ensure those working in the sex industry are staying safe.
Ms Duckmanton, 22, was a sex worker and police say they can't rule out this being related to her death.
She was last seen around the Peterborough and Manchester St area, a common place for those in the industry to work.
NZPC representatives were out in the area on Wednesday night, talking to street-based workers about safety.
Regional manager Annah Pickering told Paul Henry the workers are "very organised" and use a variety of strategies to keep safe.
These include closed Facebook groups, where prostitutes share information about dangerous clients, which then gets passed on to police.
They are vigilant about taking down registration numbers of clients' cars, and will leave DNA like hair or chewing gum in a vehicle so it can be traced later.
"Street-based sex workers are great informants amongst the community," Ms Pickering says.
Since prostitution was decriminalised in 2003, "our working relationship [with police] is better and sex workers feel more confident to pass information to the police", she says. "We've been successful in catching bad people."
Ms Pickering says Ms Duckmanton's death is a tragedy for the tight-knit community in Christchurch, which has seen three other prostitutes murdered since 2005.