Preface The transportation system is often referred to as the nation’s “lifeblood circulation system.” Our complex

system of roads and highways, railroads, airports and airlines, waterways, and urban transit systems

provides for the movement of people and goods within and between our densest urban cities and the most

remote outposts of the nation. Without the ability to travel and to transport goods, society must be

structured around small self-sufficient communities, each of which produces food and material for all of its

needs locally, and disposes of its wastes in a similar manner. The benefits of economic specialization and

mass production are only possible where transportation exists to move needed materials of production to

centralized locations, and finished products to widely dispersed consumers.

Traffic engineering deals with one critical element of the transportation system: streets and

highways, and their use by vehicles. This vast national system provides mobility and access for

individuals in private autos, goods in trucks of various sizes and forms, public transport in buses, bicycles,

and pedestrians.

Because the transportation system is such a critical part of our public infrastructure, the traffic

engineer is involved in a wide range of issues, often in a very public setting, and must bring a wide range of

skills to the table to be effective. Traffic engineers must have an appreciation for and understanding of

planning, design, management, construction, operation, control, and system optimization. All of these

functions involve traffic engineers at some level.

This text focuses on the key engineering skills required to practice traffic engineering in a modern

setting. This is the fourth edition of this textbook. It includes material on the latest standards and criteria

of the Manual on Uniform Traffic Control Devices (2003 Edition and forthcoming 2010 Edition), the

Policy on Geometric Design of Highways and Streets (2004 Edition), the Highway Capacity Manual (2000

Edition and forthcoming 2010 Edition), and other critical references. It also presents both fundamental

theory and a broad range of applications to modern problems.

The text is organized in five major functional parts:

• Part 1- Traffic Components and Characteristics

• Part 2 – Traffic Studies and Programs

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• Part 3 – Freeways and Rural Highways

• Part 4 – The Intersection

• Part 5 - Arterials, Networks, and Systems

This text can be used for an undergraduate survey course, or for more detailed graduate courses. At

Polytechnic Institute of New York University, it is used for two undergraduate courses and a series of three

graduate courses.

As in previous editions, the text contains many sample problems and illustrations that can be used

in conjunction with course material. A solutions manual is available. The authors hope that practicing

professionals and students find this text useful and informative, and they invite comments and/or criticisms

that will help them continue to improve the material.

What’s New in This Edition

This edition of the textbook adds a significant amount of material, including, but not limited to:

1. New homework problems for most chapters.

2. New chapters on Traffic Flow Theory, Analysis of Arterials in a Multimodal Setting, Critical

Movement Analysis of Signalized Intersections, and Traffic Impact Studies.

3. Material from the latest editions of key traffic engineering references, including the Traffic

Engineering Handbook, the Manual of Uniform Traffic Control Devices, the Traffic Signal

Timing Handbook, and the Policy on Geometric Design of Highways and Streets.

4. Substantial material from forthcoming new editions of the Highway Capacity Manual (2010) and

Manual of Uniform Traffic Control Devices (2010) obtained from research documents, draft

materials, and other source documents has been included. Since some of this material has not yet

been officially adopted, it provides a preview, but not final information on these standard

documents.

5. New material on actuated signal systems and timing has been added.

6. New material on coordination of signal systems has been added.

7. Reference links to important web-sites have been added, as has demonstration solutions using

current software packages.

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Roger P. Roess

Elena S. Prassas

William R. McShane

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