Eddie Jones intends to stand down from his role as England head coach after the 2019 Rugby World Cup, regardless of the team's performance in Japan.
Jones has enjoyed a sensational start to his time in charge of England, overseeing 13 Test wins from as many matches in 2016 after being appointed to succeed Stuart Lancaster.
World Cup glory is an obvious long-term goal for the Australian, but he does not anticipate staying on after the next global showpiece.
"Four years is enough. It is quite emotionally draining," he told The Times.
Jones also expressed his amazement at what he perceives to be an over-the-top reaction to Dylan Hartley's latest disciplinary trouble.
Having been praised for his leadership of England, Hartley's year ended on a sour note when he received a six-week ban for striking Leinster's Sean O'Brien in a European Champions Cup game - taking his total time serving suspensions to a remarkable 60 weeks.
Jones told The Times: "Dylan was going to be Sir Dylan Hartley and the captain of the Lions; he makes one bad decision in a tackle choice and now he is the greatest dunce in English rugby. Everyone wants to get rid of him. He is the evil at the root of English rugby. It is quite incredible.
"The thing about Dylan is he loves rugby, he loves playing for his club, playing for his country. Let him pay the penalty and get on with it."
Each player is judged on their merit
Hartley will be available for the start of the Six Nations and, while Jones stopped short of guaranteeing he will keep the captaincy, England's coach insisted the 30-year-old is not in the "last-chance saloon".
"We pick the best 23 and if he's in the best 23 then he has a chance to be captain," said Jones.
"Discipline is not a black-and-white situation. Each player is judged on their merits, some players in our squad have already had more than one chance.
"Is Dylan in the last-chance saloon? No. But he also understands that he can't behave the way he did."