The invention is directed to ensuring vehicle occupant awareness, in particular driver awareness.lt checks whether an event will change an operating characteristic of the vehicle, and determines an extent of time remaining until an estimated occurrence of the expected event. The process to inform the occupant/driver is determined based on the determined extent of time remaining until the estimated occurrence the expected event, and subsequently performed. The invention is in particular intended to provide a timely warning to a driver to overtake the driving task when switching from autonomous to manual driving.