Abstract
A technique of recording vehicle registration numbers on film has been used to study southbound car flows between Preston and Luton on the M1 and M6 motorways. Filming was performed at 4 sites: Luton, Coventry, Cannock and Preston. Analyses of lists of registration numbers recorded showed that between 14 and 32 per cent of the car flow at each site passed through one of the other sites during the hours of filming. (Author/publisher)