Abstract
This paper focuses on the concepts of drowsiness, fatigue and inattention and the objective measurement of these processes while driving a vehicle. The major aim is to point to factors that are important in order to develop effective countermeasures against these human problems, including systems that continuously assess the driver's state and the quality of driving, which record online biobehavioural data of the driver and vehicle-based performance data. A selection of recent works on the effectiveness of the various types of countermeasures being studied is provided. Finally, problems that affect most of the research in these fields are noted. (Author/publisher)