Golf's two biggest professional tours have announced a new "strategic alliance", saying that it heralds a new era for the global game.
The US-based PGA Tour is joining together with the European Tour, based in the UK at Wentworth.
They will collaborate on commercial opportunities and international media rights.
The deal will also affect scheduling, prize funds and playing opportunities for members of both tours.
As part of the deal, PGA Tour commissioner Jay Monahan will serve on the board of the European Tour.
"This partnership is an historic moment for the game of golf," said European Tour chief executive Keith Pelley.
"It is a fantastic opportunity for both the European Tour and the PGA Tour to explore ways to come together at the very pinnacle of our sport and work in unison for the benefit of the men's professional game."
Monahan added: "We are thrilled to announce this further strengthening of our partnership with the European Tour, and we look forward to working together for the benefit of the men's professional game and for golf fans around the world."
It is a move that makes perfect sense. There was little to be gained from the two circuits acting as rivals.
The PGA Tour is a far bigger and better resourced entity and attracts the largest prize funds and best known players.
But the European Tour has a rich history and a global footprint that stretches way beyond its continental boundaries. The Rolex Series of big money tournaments are significant European Tour assets.
This strategic alliance would suggest a more cohesive calendar going forward on both sides of the Atlantic.
Whether it eventually leads to a full takeover by the US tour is another matter. Such a move would need 75% support from the players who are members of the European Tour.
The disclosure that the European Tour have been in talks with the private equity backers of the rebel Premier Golf League provides a significant backdrop to the announcement of the new partnership.