Gatland is spending countless hours watching footage of fellow Pool A teams, tournament hosts England, two-time champions Australia, Uruguay, and Fiji, and preparing for every potential scenario, after being drawn in what is expected to be the tournament's most tightly contested pool group.
Gatland believes Fiji cannot be underestimated and says finalists could be determined on points differential, while he is also concerned about how Wales can best handle the short turnaround's between their opening three games.
"Pretty much all the time really," Gatland said of his hours spent analysing rival teams.
"I don't think any of us can underestimate Fiji. They are going to be really tough proposition, a real handful.
"You're thinking, potentially, is this a pool that might come down to points difference, and you've got to keep that in the back of your mind.
"The thing we've got to plan for is the short turnaround. We play Uruguay and six days later we've got England, and then five days later we've got Fiji.
"So that Fiji game, [I'm looking at] how do you mix and match your squad and try and keep players fresh. So there's a lot of thought that's gone into it.
"All of the coaches do that, you're thinking all the time about the possibilities and going through all the scenarios."
Gatland concedes he has made calculated risks in naming five locks and selecting two players in his 31-man squad who remain under injury clouds, with tighthead prop Samson Lee working his way back from a ruptured Achilles tendon, and fullback Liam Williams still overcoming a broken foot.
He had some sympathy for injured Kiwi playmaker Gareth Anscombe, who missed selection due to an ankle injury, but said he could still come into calculations if injuries forced them to make changes.
"Every squad that's named there's always a risk element that you're going to be a little bit short potentially somewhere," he said.
"That's part of your planning; you're talking to your medical team about how soon they're going to be available.
"Samson Lee is up and running at the moment, he's doing live scrummaging, so he's not too far away from taking a full part.
"Liam Williams is back running a little bit now so they're not too far away those players."
"Gareth Anscombe's got an ankle injury at the moment and the medic's said that's a three to five week injury, and if he'd be fit he probably would have made the squad.
"We weren't certain when he'd be fit and available but if we do pick up injuries someone like that is hopefully going to be pretty valuable to us."
Having a core group of veteran forwards to rely on was a positive, while Gatland is also enthused about the blend of youth and experience throughout his squad.
"It's hugely important [having experience]. Particularly that loose forward trio of [Sam] Warburton, [Taulupe] Faletau and [Dan] Lydiate.
"They've been together for a number of years now, and Alun Wyn Jones and Gethin Jenkins at loosehead, so we're pretty lucky.
"We've got a nice balance at the moment with experience and some exciting young players."
