Despite the availability of cheap, fast, accurate and usable eye trackers, there is little information available on how to develop, implement and use these systems. This 2nd edition of the successful guide contains significant additional material on the topic and aims to fill that gap in the market by providing an accessible comprehensive introduction. Additional key features of the 2nd edition include: Technical description of new (state-of-the-art) eye tracking technology (new chapters 9, 10, and 11); a complete whole new Part describing experimental methodology including experimental design, empirical guidelines, and 5 case studies (new chapters 13, 14, and 15); survey material regarding recent research publications included within Part IV. This second edition is a invaluable guide for practitioners responsible for developing or implementing an eye tracking system, as can also be used as a teaching text for relevant modules on advanced undergraduate and postgraduate courses.