Cross-centreline head-on crashes are one of the most severe crash modes due to the large closing speed between the two opposing vehicles. Two countermeasures, centreline rumble strips and lane departure warning systems, aim to help reduce the frequency of head-on crashes. However, both of these countermeasures rely on proper action by the driver of the encroaching vehicle. The purpose of this paper is to analyse event data recorder information from real-world cross-centreline head-on crashes to help understand how the drivers of the encroaching and impact vehicles react before impact. Most drivers that reacted before the crash simultaneously performed a braking and steering manoeuvre. The driver of the impacted vehicle was more likely to react before the crash than the driver of the encroaching vehicle. Every driver of the encroaching vehicle that performed a steering manoeuvre turned back towards the correct lane of travel.