O'Brien hosts final '7.30 Report'
The 65-year-old Australian television personality, who has been the editor and presenter of the current affairs show since it first aired in 1995, announced in September that he would be leaving the programme to host Four Corners next year.
O'Brien said on his final show: "A lot has happened since [the start], the tragedies and the triumphs, the big landmark moments and the little things that nonetheless brightened our lives.
"I've enjoyed your company and I hope you've enjoyed mine. The time has come to say goodnight."