Kava is a traditional Pacific Island drink with great cultural significance that produces soporific, relaxant effects similar to sedative drugs. Concerns are increasing over the use of kava and sedative drugs and their impacts on driver ability and road safety. Most of the 20,000-plus kava users in NZ are consuming this substance at volumes 32 times greater than pharmacologically recommended doses, with many then driving home. Injury resulting from road traffic accidents is the leading cause of hospitalisation for Pasifika men and women living in NZ with anecdotal reports suggesting that kava contributes to this. This study builds significantly on previous research. It will use a sophisticated somato-sensory measure providing detailed neuroscientific knowledge to understand driver fitness during and immediately following high kava use. This research will improve health outcomes for Pasifika peoples and other road users.