Dozens of police officers are taking to Nottingham's buses and trams to catch fare dodgers and troublemakers.
During an eight month period last year, there were 40 assaults on Nottingham City Transport staff and vandalism cost the company more than �100,000.
On the trams, five members of staff are subjected to physical assault in an average month.
On Friday 25 officers are boarding buses and trams and anyone causing problems faces an on-the-spot fine.
They will also be looking out for motorists who use bus lanes illegally.