Electronic toll collecting reduces traffic congestion at toll lanes and makes it easier for users and toll collectors. In Portugal and the United Kingdom, after flirting with different kinds of tolls on privatized highways, shadow tolls are being increasingly utilized. Shadow tolls are payments by the public sector to the private sector based on road usage, which eliminates the need for intermittent physical tolling on the highway.
An evolving approach to tolling being used in a PPP led by Fluor[xxix] for the Virginia I-495 Hot Lanes is "congestion pricing". Congestion pricing means tolls will be collected electronically on a sliding scale depending on the day of the week and time of day to compensate for traffic loads.