This report is an Informational Guide for highway agencies on the use of low-cost improvements to alleviate operational problems on two-lane highways. The Guide addresses both passing and turning improvements that can be constructed for a lower cost than construction of a continuous four-lane highway. The passing improvements presented in the Guide include passing lanes, climbing lanes, short four-lane sections, turnouts, shoulder driving, and shoulder use sections. The turning improvements included are intersection turn lanes, shoulder bypass lanes, and two-way left-turn lanes. Design and traffic control guidelines presented for these improvements include location and configuration guidelines, geometric design criteria, recommended signing and marking practices, and operational and safety effectiveness estimates.

First Published in 1989. Routledge is an imprint of Taylor & Francis, an informa company.

A replacement to the publication entitled 'Highway design and operational practices related to highway safety', also known as 'The Yellow Book', and most recently published in 1974.