While still a national pastime, "saunas are less common now in politics and business, due to lack of time," Maria Romantschuk, the spokeswoman for Finland's woman president Tarja Halonen, told AFP.
"People who are in senior positions in politics and especially in business are more likely to be technocrats today than they were 30 years ago," when grass roots politics was more common, said Olli Rehn, the Finnish EU enlargement commissioner who is a big fan of saunas.
"Europeans often think that 'sauna diplomacy' is a form of torture. That's wrong. It's an act of reflection and relaxation. And it's excellent to negotiate without any pressure," he said.
But Rehn conceded that with increasingly "more emphasis on gender equality" in politics, the custom was no longer always possible. "It is difficult to organise a sauna for the men on one side and the women on the other."
A sauna in Finland is typically taken in the nude, and as a result men and women take separate saunas. Mixed saunas exist but only among close friends and family. In cities, saunas are often built as a separate room in a house or apartment building, while in the countryside they are typically constructed as a small wooden cottage by a lake for a quick dip in between sweat sessions.
In a society where men have traditionally been depicted as heavy-drinking macho types, the sauna was until recently a way of confining women to subordinate roles, said Kirsi Seppalainen, a senior business executive.
"In one of my previous jobs I was the only woman attending management meetings, so I always had to find something else to do when the men were in the sauna. And then sometimes it happened that I afterwards heard that they had agreed on something in the sauna," she said.
However, "I think this is changing," Seppalainen said.
Heidi Hautala, an MP for the Greens Party who often takes saunas with party colleagues to hammer out policy, agreed that change was afoot.
"Sauna politics and business are not what they used to be.
"One reason for the change is women's increasing participation in seminars and company retreats through our better access to managerial and top posts in business and politics," she said.
"Of course some organizations still think they can afford the old style but I would say that they are going to discover very soon that they are out of date," Hautala noted.
For many Finns, sweating it out in the sauna is seen as a good way of "personalising" a professional relationship.
"If you discuss and agree on something when you are all naked, it's difficult afterwards not to keep your word. It's a social thing that lowers defenses," said Euro MP Lasse Lehtinen, another politician known for enjoying a good steam.
Once upon a time, taking a sauna together was almost a prerequisite before any business deal could be negotiated, some say.
But nowadays, a sauna with a client is more likely to be done after the ink on the contract has dried.
"You make decisions and then get to know your customer, (taking the sauna when) it's time to relax," said Tiia Sammallahti, head of communications at the hotel chain Palace Kaemp Group.
Lehtinen said globalisation had also complicated the sauna tradition, as negotiations are sometimes held with people from different cultures who might not accept nudity.
Rehn revealed that he shared a sauna with the main negotiator for Turkey's European Union membership talks, Ali Babacan, last summer at his countryhouse.
"Babacan was on a private visit to Finland with his family. We naturally took a sauna with him and his son. It was very nice. They like it a lot," Rehn says.
While it may have been enjoyable for Babacan and Rehn, the hot steam apparently didn't do much for Turkey's membership talks, which were frozen several months later.
Head of state Halonen, meanwhile, has had to break with the tradition of presidential saunas her predecessors organised when they received official guests.
"The president likes to take a sauna but she doesn't do it with visiting dignitaries," her spokeswoman Romantschuk said.So when Russian President Vladimir Putin visited the country in 2005, he sweated it out with Halonen's husband instead.
- by Gael Branchereau