Driver behavior and performance have been studied extensively in the last decades. Researchers have developed theories and models of driver situational awareness, driver decision-making and errors, information processing, and mental workload. Meanwhile, other scholars have focused on creating and optimizing in-vehicle technology-based interventions to increase safety. The purpose of this special issue is to bring together a collection of empirical and theoretical work focusing on understanding Driver Behavior and Performance in an Age of Increasingly Instrumented Vehicles. Several themes characterize this special issue: