World Rugby chair Brett Robinson told AFP that the sport "can't sit still" if it wants to grow, including conquering the "challenge" that is the United States with the 2031 World Cup.
Rugby union's place in global sport's pecking order has come into sharp focus over issues such as financial sustainability, player welfare and threats to its popularity in traditional rugby heartlands.
All Blacks great Michael Jones told AFP last week that union is losing the battle for "hearts and minds" to rival code rugby league in New Zealand.
His comments came just before Auckland-based Moana Pasifika said that it would fold at the end of the season, becoming the second Super Rugby team to go under in three years because of financial problems.
In Wales, another traditional rugby country, the national team's fortunes have nose-dived and football has caught the public imagination instead.
"I think that rugby is broadly in really rude health," Robinson, an Australian former international, said in Hong Kong, where he was attending the city's sevens tournament.
He pointed to participation rates around the world, including two million women, saying that the sport is "truly international".
He added: "We have to protect our core (markets), but we can't sit still and believe that the game will thrive if we don't consider and continue to look at how we grow the game."
That means taking rugby to new frontiers, prime among them the United States.
Australia will host the men's Rugby World Cup next year and the women's event in 2029.
Then comes the United States, staging the men's showpiece in 2031 and the women's competition two years later.
The US will host the football World Cup this June-July, providing a taste of the kind of challenges that rugby chiefs could encounter, with ticket prices and transport costs making headlines for the wrong reasons.
'CHALLENGING MARKET'
Serious doubts have surfaced over the health of rugby in the US, including the state of the men's national team and the professional Major League Rugby, down to six teams after four clubs quit the competition.
Reports in British newspapers claimed that there were questions over how the US would deliver the World Cup on a commercial level.
Robinson said that it was about "building momentum into '31".
"We have worked with the top unions around taking iconic events and matches over that period of time (to the US) to build connections to fans.
"And also we currently have 27 host cities that we're focused on that we'll probably whittle down to 12 to 14 that we will look to base the matches in."
The host cities will be announced after the 2027 World Cup.
As part of efforts to spark excitement towards 2031, South Africa and New Zealand will clash in Baltimore in September. Ireland faced the All Blacks in Chicago last year.
"We're working really hard to build a long-term play," Robinson said.
He added: "We aren't sitting still in terms of preparing and acknowledging that it's a challenging market.
"But equally as important will be what happens in '33 because women's rugby in North America is going from strength to strength."
Before that comes the World Cup in Robinson's native Australia next year, and he said that initial ticket sales "exceeded all expectations".
More than 750 000 tickets were snapped up for the largest edition of the World Cup, with 24 teams.
"So it's a really good signal about the World Cup," he said.
"We're really optimistic and excited," he added.
"Obviously there's some recent uncertainty that everyone's feeling through the Middle East (war), but we're still quite buoyant about the scale of what that event's going to look like."