Tired of the Three Lions floundering on the biggest stage, the former defender is trying to shake things up away from the field as well as on it.
Southgate wants more players to shoulder the burden of responsibility and express themselves more freely, whether that be in a match or a meeting.
Asked what he is giving his players, Southgate said: "I don't think it is about power. You have to be comfortable enough as a coach to be challenged.
"We prepare a team but the most difficult thing to do is to step over the white line and play. You have to make decisions on the field.
"We might talk through set-plays and then the opposition do something different and players have got to react to that in an instant.
"You want players who are good at making decisions and if they make the wrong decisions on the pitch, then our job is to help them see how they might have done it differently and try to improve, not to kill them for making mistakes.
"But that is the sort of environment I like to create.
"Mistakes will happen in games of football - I made millions of them - but it is what you learn from those mistakes. You're a better player for going through that."
Southgate's desire to have players taking a bigger role in decision-making was welcomed by Bertrand.
No stone is left unturned tactically, the Southampton left-back says, and the coaching staff encourage players to express themselves, bringing more responsibility to the group.
They have already discussed the three-man defence and three-pronged attack that looked so promising in England's harsh 1-0 midweek loss in Germany, with Southgate looking to give a framework but avoid overloading players.
The benefits of such a tweak in approach were explained by England rugby coach Eddie Jones when he spent Friday with the group.
"I think we're creating a new culture, an open culture that is focused on being the best that we can be," Bertrand said.
"I think that comes down to working had and that was one of Eddie's main points. How to sustain it? You just have to work harder.
"As a group, we very much want to achieve things for the whole country and we all have the ability, so there's no reason for us not to.
"We're more than focused on creating a great culture. That's why it was fantastic that Gareth invited everyone, not just those who had been called up (to Monday's meeting).
"For the longevity of the team going forward, we're going to need all these players, so it's important we all buy into it and come together."
England coach Jones won his first 18 matches in charge of his adopted country, equalling the All Blacks' world record streak, and claiming back-to-back Six Nations titles after a four-year drought.
The Australian was blunt at times during his day with his footballing counterparts but Bertand called him a "massive inspiration".
"In the end, it's the players that lead," the England full-back added.
"It is the players who need to be looking after one another, making sure the expectations are constantly met.
"You have to breed that culture, it has to be 24/7. You can't just have off days and on days. It has to be constant.
"That was very much the impression we got from the rugby guys, one of their main psychologies that has driven them to achieve the success that they have had."
While drive is important, so too is a feeling of comfort - something extended to the way Southgate is addressed, with Bertrand and many of his team-mates referring to him as Gareth rather than 'boss' or 'gaffer'.
"As long as they keep it clean, I don't care what they call me," Southgate said, smiling. "I think it is outdated to be 'boss'.
"Maybe some people might view it as a sign of respect, but you can call somebody 'boss' with zero respect and you can call somebody by their name with more respect.
"To me, it makes no difference, really. It's a slightly archaic thing that we have in our game.
"In football it's engrained and we just do it, but actually why do we do that?"