By Mary Hennock BBC News Online business staff

From mid-June to September the diaries of Britain's top bosses and bankers are flooded with invitations to drink champagne and eat strawberries at Royal Ascot, Wimbledon, Henley regatta and Silverstone.

The season, as it is known, is a tough schedule of spectator sports which have become an arena for corporate schmoozing.

Getting round the track requires a hard head and an even harder heart as business associates seek to build up goodwill over trays of canapes.

Wimbledon is by far "the biggest event of the hospitality calendar," says a spokesman for Keith Prowse, one of two official hospitality firms appointed by the championship's organisers.

Big ticket

There is no point in corporate hospitality looking stingy. Even so, Wimbledon's popularity can make it an expensive day out.

Goran Ivanisevic celebrates last year's win

Two tickets for clients to watch the men's finals on Centre Court - with lunch, drinks and a traditional tea of strawberries and cream - could set you back about �6,000.

That's quite a bit more than the �4,800 it would cost to hire an antique racing yacht to host 12 people for a day during Cowes week.

The British Grand Prix at Silverstone in early July is also popular; there, a circuit-side box can cost �700-800 per person.

Mumm's the word

Not surprisingly, perhaps, companies are reluctant to discuss what they spend on Wimbledon, or how many people they invite, or why they find it worthwhile.

We're involved in Wimbledon because it's a showcase for our technology

IBM UK spokeswoman

With most of the world's major economies in a fragile recovery at best, and stock markets still jittery, big firms are setting tighter budgets for corporate junkets.

"Companies are picking and choosing the events their clients are interested in going to rather than taking out blanket hospitality for the whole season," says Jeremy Batstone of NatWest Stockbrokers.

Although the lavish style of past years has been "somewhat toned down", corporate junkets have a valuable role to play, he says.

"It provides them with an opportunity to schmooze their clients and in this environment when companies are desperate for business... any opportunity to drum up a general feeling of caring is welcome."

Showcase

The giant US computer firm IBM provides Wimbledon's scoreboards and a host of other gadgetry, including court-side radar to measure the speed of players' serves.

IBM is proud of its role as the official IT provider at Wimbledon, and willing to admit it also buys seats for clients to watch the tennis.

"We're involved in Wimbledon because it's a showcase for our technology, primarily, as well as being a great place to socialise," said a spokeswoman for IBM UK.

A tennis fan, she reckoned that, for two weeks a year at least, she had "the best job in the world".

However, she declined to give details of how many guests IBM took to Wimbledon, or anywhere else.

"We're at every event you could possibly name - Henley, Ascot, cricket events at the Oval, rugby at Twickenham, the tennis opens - and that's not an exhaustive list."

Fans get heated

Preparations for the summer schmoozing season start months ahead.

Wimbledon "literally is a year-long event" for Sportsworld, the tournament's second official hospitality provider, says marketing director Simon Gillespie.

The firm co-ordinates everything from tickets to toilets for about 4,000 guests.

Sports fans often resent the presence of less passionate corporate guests.

"After queuing for 12 hours to get in, it's more than a little irritating to see rows of empty seats reserved for corporate guests who are still eating and guzzling champagne," said one tennis fan.

Wimbledon's organisers insist that fewer than 8% of all tickets for top games on the centre court and number one court are sold for corporate hospitality.

'Good for tennis'

They say the money keeps other seat prices down and supports the sport.

"A large amount of our income is part of our surplus which goes back into the development of British tennis," says a spokeswoman for the All England Lawn Tennis Club. Last year's surplus was �32m.

Outside the hospitality - or debenture - boxes, tickets can cost as little as �5, with a seat for the finals costing �69.

The grounds contain 34 hospitality marquees and suites this year, and the Club has gradually reduced the numbers over the last decade to allow more "more tickets to be allocated back to fans, while increasing the exclusivity of the hospitality."

Exclusive or not, the season probably has limited value for those hoping to climb the corporate ladder.

They might be better off using their colleagues' absence to clinch a few high-profile deals.

"These days most companies are looking for proof of excellence rather than the ability to socialise," says Mr Batstone.

The season has changed drastically since the early years of the last century, when it was a playground for the aristocracy.

"To some extent these events have lost their cachet," he says.