In the age of information, in-vehicle multitasking is inevitable. The popularity of the automobile, in combination with the present information age, create a growing demand to do more in-vehicle than simply focus on the road. Unconstrained Design, a philosophy which supports rather than constrains multitasking, is proposed as a path toward enhancing performance in-vehicle. Situation Awareness (SA), a theory allowing designers to understand how operators interact in dynamic, complex environments, is used to frame this experimental investigation. Two SA-grounded human-machine interface concepts are proposed, designed to support drivers to multitask in-vehicle when frequent task switching is required. The first focuses upon supporting preparation for a Non-Driving Related Activity (NDRA), and the second upon supporting the Driving Related Activity (DRA) when an NDRA is active. While multitasking, Contextual Cueing, using a Head-up Display, produced significant reductions in NDRA response time, while an auditory lane keeping aid increased the amount of time a driver spent in the central region of a lane. The combined evidence suggests that using SA and Unconstrained Design to create of IVIS that support drivers’ ability to multitask in-vehicle can lead to task performance improvements.

In the driving environment, competition exists between Driving Related Activities (DRAs) and Non-Driving Related Activities (NDRAs). This is a source of inattention and human error. Continual proliferation of in-vehicle information systems (IVIS) presents drivers with opportunities for distraction. Drivers simultaneously manage DRAs alongside unrelated but cognitively demanding NDRAs. Vehicle designers need ways of understanding human capability in such situations to provide solutions that accommodate these conflicting demands. This paper proposes a framework intended to address such challenges, rooted in the widely accepted construct of Situation Awareness (SA). However, SA theory does not presently accommodate disparate unrelated goal-driven tasks performed in parallel. This framework reconciles the present reality of drivers simultaneously devoting cognitive resources to attain SA for multiple activities by proposing a separate body of knowledge for each active goal. Additionally, the process of achieving SA is expanded to incorporate this concurrent development of separate bodies of goal-directed knowledge. The advantage of reconceptualising SA for driving allows consideration of interface design which minimises the impact of competing activities. The aim is a framework facilitating creation of IVIS that help drivers succeed in multi-goal multitasking situations. Implications of the proposed framework for theory, design and industry-driven automotive safety efforts are discussed.