Entering the 21st century, the Nation's transportation system has matured; it only expands its infrastructure by a fraction of a percentage each year. However, congestion continues to grow at an alarming rate, adversely impacting our quality of life and increasing the potential for accidents and long delays. These are expected to escalate, calling for transportation professionals to increase the productivity of existing transportation systems through the use of operational improvements. In order to assess the potential effectiveness of a particular strategy, it must be analyzed using traffic analysis tools or methodologies. The objective of this book is to assist traffic engineers, planners, and traffic operations professionals in the selection of the correct type of traffic analysis tool for operational improvements.