This Travel Time Data Collection Handbook provides guidance to transportation professionals and practitioners for the collection, reduction, and presentation of travel time data. The handbook should be a useful reference for designing travel time data collection efforts and systems, performing travel time studies, and reducing and presenting travel time data. Agencies new to travel time data collection may wish to adopt sections of the handbook as standard procedures, whereas agencies with data collection experience may wish to incorporate specific details or criteria. Initial chapters of the handbook describe how to design data collection activities, including the determination of parameters such as study size and scope, data collection technique, and other critical study elements. Chapters 3 through 6 include a description of each data collection technique, major advantages and disadvantages, cost and equipment requirements, and step-by-step instructions. Related experience with the data collection techniques is included for examples of applications. Chapter 7 provides guidance for reducing travel time data and preparing tabular and graphical presentations.