Managed motorways in the United Kingdom are motorways which use active traffic management. Their aim is to increase traffic capacity at times of peak traffic flow. They use variable speed limits and hard shoulder running at busy times. A "hard shoulder" is an inner lane which in normal times is only used for emergencies.
Benefits include smoother traffic flows, more reliable journey times, fewer road traffic collisions, and reduced noise and harmful vehicle emissions. Where only variable speed limits are used, it is called a controlled motorway.