Updated Monday, 15th February 2021, 7:39 am But top officers from the National Crime Agency (NCA) say sites such as Vivastreet and Adultwork can also help to keep women off the streets and safe. Rob Richardson, head of the NCA’s Modern Slavery and Human Trafficking Unit, said the sites are widely used to target punters by criminals who fly their victims into the country and force them to sell their bodies for sex. He said: “We recognise that adult services websites (ASWs) are a significant enabler, and if we are looking at the internet as an enabler of exploitation then ASWs provide the lion’s share of that.