Agents, translators, press, coaches and, yes, players. It is August and the flesh market is in business.
Celtic have picked another two players from the throng and the selections are both intriguing and instructive. Alex Tonev, 24, on loan from Aston Villa, with a view to a permanent £2m deal and Jason Denayer, 19, on loan from Manchester City, are the latest recruits with Ronny Deila, the Celtic manager, confident he can bring in a forward for the Champions League play-off tie against Maribor next week.
The acquisitions of Tonev and Denayer have excited Deila, who has encountered predictable difficulties in the transfer market. He is candid in his assessment of how he and Celtic can recruit players to improve the team and frank in his acknowledgement of precisely where he has to shop.
Of Tonev, he said: " He is quick, shoots with both feet, two-footed, a winger who can also play No.10 and in the midfield but I see him more as a winger. He has the qualities we are looking for. He is has not been playing much at Aston Villa and this is a new chapter for him to get his confidence up and get back to the level he was at at Lech Poznan where he did very well."
Tonev has a slight injury and possibly will not feature until the second leg of the tie against Maribor, Legia Warsaw appeal permitting.
He was more expansive on Denayer, a central defender he has followed for some time. The headline news is that Deila believes the teenager is already outside Celtic's budget. He said with a smile: "We could get an option to buy but I don't think we have enough money. Jason is going to be worth a lot of money.He is already worth a lot of money. Is he a player worth £6m or £7m? I'd say he's worth more, maybe £10m."
Asked if Denayer could become worth £15m-£20m, Deila added: "Yes, he could. He's a very good player and he will have a great future - people will see it when he plays."
He will go into the team quickly, perhaps even against St Johnstone tonight.
The signing of both players is a product of years of work by both the scouting department and of Stromsgodset, Deila's previous club, having a relationship with Manchester City. The English club, buoyed by Abu Dhabi fortunes, has sought clubs to place players on the fringe of the first team. Stromsgodset filled that bill in Norway, now Celtic have picked up Denayer on a similar deal.
Deila has a professional friendship with Patrick Vieira, the former French player who is development executive with City. The Norwegian has talked extensively with Vieira and watched Denayer, saying: "It is not always that you know a lot about signings, but him I know a lot about."
The Belgian has attracted comparisons to his countryman Vincent Kompany, and if this is premature, possibly fanciful, he has gained a reputation already. He fits the Celtic model of affordable and capable of improvement.
Crucially, too, he agreed to come. This is not as straightforward as it seems. Deila pointed out that Jeff Louis, the Nancy midfielder, had rejected a move to Glasgow, preferring to join Standard Liege.
"We were offering more money than Standard Liege but he wants to go there instead of us," he said. "It has to be something about not wanting to come to Scotland and preferring to be in Belgium. It is very important that we understand the language, what is happening here. It is different. We are not Premier League, we are playing in Scotland and that is why a talented player can be easier to get than the big player. And the big players have salaries that are three, four, five times bigger than you can get here. That is the main issue."
Deila, then, has to be creative and perhaps patient. He talked of acquiring another player but pointed out that his transfer strategy had to bow both to the reality of budget but to his unfamiliarity with the elevated market in which he was now shopping.
Intriguingly, he also talked about bringing back expatriate Scotsmen to the club when they had made their mega money elsewhere. There may be few candidates in this bracket but it is a sign of how Deila is thinking deeply about the avenues open to him.
"Scotland has been a little bit like Norway," he said. "In the 1990s you had so many players abroad and brought them home back in the last few years there has not been so many any more."
He added: "That is also why you have to start with the youths. Get the youths in, make them good enough and then big clubs will buy them for a lot of money. They go out and then we can bring them back again. I think things will turn in that direction, that's how it is."
There was no protest in this, merely an acknowledgement about how he and Celtic must go about their business. Denayer, he believes, will improve as a player at Celtic but, more pertinently for the Scottish champions, will increase the quality in the squad and show the younger players where the bar must stand.
Deila, who has lost Fraser Forster to Southampton for £10m, is confident he can face the season with Craig Gordon and Lukasz Zaluska as credible contenders for the goalkeeping spot.
He may yet, of course, have to sell another player. What are the prospects of Virgil van Dijk, the Dutch defender, staying at Celtic? "I think we are done in this window but again you never know in football, it's about money."
The hubbub in the foyer was further testimony to his belief that money does not talk in football, it shouts.