( CNN ) -- The case of three women held as slaves in south London has shocked not just the British public , but people across the world . What makes this particular case stand out is the length of time these women are said to have been held captive - over 30 years . Although this is an extreme example , this type of slavery is not uncommon in London . Figures from the United Kingdom Human Trafficking Centre and Serious Organised Crime Agency for this year show that there were 389 potential victims of trafficking in the capital . Although the women in this case are not believed to have been trafficked , the case shows that hidden slavery is taking place around us , within our everyday environments , whether it be on construction sites , mobile soup runs for the homeless , at cheap takeaways , in nail bars and in domestic homes in our neighborhoods . Read more : How to recover after decades of slavery ? It 's not necessarily organized by criminal gangs - it can involve informal arrangements , carried out by so-called ordinary and even respected people in the community . I recently published a report called `` Shadow City -- Exposing human trafficking in everyday London '' that uncovered just how diverse that trafficking is , and that no matter where you live you are probably not that far from someone who is being exploited . Sadly , authorities are still blind to this . Things need to change , urgently . An overstretched anti-trafficking unit in London 's Metropolitan Police , and a figure-driven culture , means police are focusing on large-scale organized cases , and neglecting the informal cases that take longer to find , but are sometimes more serious . In this case the three victims were lucky . They are said to have contacted a charity that was able to successfully rescue them . Many are not so fortunate . Read more : Slavery 's last stronghold . But if we continue to lose the expertise of dedicated trafficking officers within the Met police , the cultural subtleties behind cases will be missed and traffickers and perpetrators of slavery will continue to largely evade conviction . Of course budgets are tight , but if the money made in trafficking exploits is recuperated through the use of specialist teams , then these investigations could pay for themselves . In my report , I made some recommendations that could help tackle the lack of action on informal types of slavery . These included the Met 's anti-trafficking unit being urgently protected from further integration into other units , additional human trafficking units to be established in other police forces across the UK , human trafficking to become part of the core syllabus for training new police recruits , and special points of contact to be established in every borough 's police force . The police are not the only agency that needs better systems put in place . It is also vitally important that social workers , teachers , health professionals and benefit agency staff receive training on how to spot signs of trafficking and slavery , and who to consult if they have concerns . For too long many Londoners have assumed that trafficking happens elsewhere , and statutory agencies have concentrated too much resource into trafficking that happens through organized crime with a concentration on drugs and sex workers . The case in south London shows that slaves could be living next door . Read more : The CNN Freedom Project . Watch more : 12,000 girls rescued from slavery . The opinions expressed in this commentary are solely those of Andrew Boff .
The case of three women held capitive in London has shocked Britain , and the world . While it 's an extreme example , slavery is not uncommon in London , Andrew Boff says . Authorities are over-stretched and neglecting the informal cases which are hard to find . This case shows how slavery is a huge problem -- and it 's all around us .