Martin, it would be interesting to know what the police response to this incident has been. If I may be so bold, I have a few suggestions: First up, the eyes and ears of the Sainsbury's car park are surely the car washers (plus trolley collectors) - I have driven in to the car park and they clock every car. They would be the first people to talk to. If you have a photo of the car take it along - their English isn't great in my experience. Second, did you approach Sainsbury's and/or the car park owner about CCTV? What about the nursery? Any CCTV on Dog Kennel Hill (bound to be)? Did you get anywhere with them? The fact that you know within a 15 minute window when the car was taken would make a trawl of recorded footage very easy - but move quickly before it is deleted. Thirdly, if you haven't already done so it might be worth putting a call in to the local Safer Neighbourhoods police team. You could do worse than specifically ask them to request a check of ANPR (Automatic Number Plate Recognition) cameras for your number plate (including but not limited to the congestion charge cameras - there are ANPR cameras everywhere, esp. on larger roads into/out of London, plus the whole motorway network). Speed and bus lane cameras too. Also, ask the police about any other recent car crime in the Sainsbury's car park, especially cars being stolen. If it's a routine problem the police are more likely to respond. If you aren't happy with the police response contact your councillor. Good luck - and let us know how you get on. Gavin