World Rugby's council will be at least one-third female from next year, the international federation has announced.
In a move described as "transformational", 17 new members will be added to the game's highest decision-making body.
This will be achieved by asking the 11 unions and six regional associations with additional votes on the council to nominate an additional representative on one condition: they must be a woman.
This will mean all the main rugby-playing nations will have three representatives and three votes, while Japan and the six regional associations have two representatives and two votes. The changes will increase the council from its current membership of 32, all of whom are men, to 49.
In a statement, World Rugby chairman Bill Beaumont said: "The reform is historic, reflective of our ambitions and long overdue. If we are to promote and nurture the growth of women in rugby then change must be led from the top."
The change was agreed at a recent meeting of the council in London where it also approved the "2015-25 Women's Plan", a global strategy to grow the women's game on and off the pitch that includes a review of the competition calendar and more development money.
Katie Sadleir, World Rugby's general manager of women's rugby, said: "Building on the success of the recent Women's Rugby World Cup in Ireland, the decision to increase the representation of women on council to more than a third is transformational for rugby.
"It will change the way we govern the sport going forward, making a difference not just for women in rugby but for all of rugby."
And just to demonstrate that it means business, World Rugby announced that Ada Milby, the secretary general of the Philippine Rugby Football Union, has become the first new councillor, having been elected by Asia Rugby last weekend.