Safety barriers are being installed at the top of some large multi-storey car parks in Peterborough city centre.
The work to put the new structures on the top of Queensgate car parks started this week.
The works have started following a number of incidents where people have died after falling from the buildings. Four people died between April and September last year.
The works will be completed early next year.
A spokesman for Queensgate Shopping Centre said the construction was being carried out in a way which would prevent disruption for shoppers.
He said: “We are undertaking an enhancement programme to optimise customer safety within the Queensgate Shopping Centre car parks.
“These works are being phased to limit customer disruption and to ensure we retain full parking capacity during the peak trading periods.
“The first phase is due to be completed by November this year and the second phase by March 2016.
“This builds on our extensive £10m refurbishment which was completed in 2014, where car parks were upgraded with low energy lighting system, state of the art CCTV and a complete redecoration.”