Targeted adverts no longer just online
30 July 2013 Last updated at 01:07 BST
Targeted adverts - based on web browsing history - have caused quite a reaction. Search for a product and adverts could be appearing next to your emails for months. But what if this was possible in your offline life?
Adverts in petrol stations, in big stores and in shopping centres are beginning to use facial recognition to tell age and gender, making it easier to see who the advert is reaching and who it should be targeting.
Marc Cieslak discovers what adverts he would be watching when the adverts themselves know who he is.
The programme was first broadcast on Saturday 20 July 2013.