POLL: Do you agree with smart motorways?
The M4 is currently being converted into a 'smart motorway' from Junction 12 (Theale) to Junction 3 (Hayes).
This means the hard shoulder will be removed to create a fourth lane.
Highways England says: "This means there will be an additional lane for traffic which will increase capacity and reduce congestion, more technology on the road to smooth traffic flows and manage incidents and more reliable journey times."
The work on the M4 is due to be completed in 2022 and will cost £848m.
Do you agree with smart motorways? Vote in our poll: