This publication contains detailed guidelines for the planning, conduct, and use of safety engineering studies at identified hazardous locations. The publication should be beneficial to highway engineers and other professionals involved in highway safety and/or traffic operations. The objectives of this publication are to: (1) plan an effective highway safety engineering investigation of an identified hazardous location; (2) perform a highway safety engineering investigation of an identified hazardous location, using appropriate procedures and techniques; (3) select the most appropriate procedures and techniques required for safety engineering studies, considering agency size and type; (4) identify safety deficiencies and feasible countermeasures that are necessary to alleviate the hazardous situation; and (5) select a safety project based on safety objectives.

This guide provides a practical step-by-step procedure that can be used to identify, analyze, and correct safety deficiencies on relatively low volume roadways.

TRB's National Cooperative Highway Research Program (NCHRP) Report 672: Roundabouts: An Informational Guide - Second Edition explores the planning, design, construction, maintenance, and operation of roundabouts. The report also addresses issues that may be useful in helping to explain the trade-offs associated with roundabouts. This report updates the U.S. Federal Highway Administration's Roundabouts: An Informational Guide, based on experience gained in the United States since that guide was published in 2000.