A man was airlifted to hospital with serious injuries after a crash on the A41 on Sunday evening.
The accident, which involved two vehicles, happened at the Waddesdon crossroads just after 6.30pm.
The man was released by firefighters from his vehicle using hydraulic rescue equipment, before being transported by air ambulance to the John Radcliffe Hospital in Oxford.
The road was closed in both directions at Quainton Road while officers examined the scene, before it was re-opened at 11pm.
A woman was released injured before the fire service arrived on the scene.