Just when you thought that City law firms could not get any more entertaining, they launch their seasonal charm offensive.Clients are being buried under a huge pile of invites, as law firms do their best to thank them for their busines s.

But it seems few clients are complaining about the endless social whirl their law firms are subjecting them to.Although Wimbledon and Ascot remain as popular as ever, there is some evidence that law firms are racking their brains to come up with new ideas for corporate hospitality.Consider US firm Gibson Dunn & Crutcher, and its recent party designed to put its new City office on the map in a way that lawyers would not expect.

It laid real grass on the office floors and featured sado-masochism.

Or Nabarro Nathanson's 'Goodbye to David Bramson' Monopoly party, where the firm marked the retirement of its senior partner atop a specially made giant board game.Now it is summer - a good excuse for firms to celebrate.

The latest bash on the social calendar was Eversheds' annual do at the Royal Academy.

But it is not all champagne, culture and ice sculptures for long-suffering clients, who will have been dragged around golf courses and forced to watch hours of tennis and cricket once they had recovered from the soccer season.While the sporting events tend to be partner-led initiatives, some firms are finding ways of adding more value to their get-togethers.

Landwell banking partner Celia Gardiner says the firm's recent 'Coctel Latin American' theme party was about networking, and not just between lawyers and clients, but also between the clients themselves.'I wanted to do something to bring together the contacts I've got,' says Ms Gardiner, who joined Landwell from Norton Rose last year.

'On a personal level, I'm a great believer in networking.

The reason someone is going to come to me is because I'm offering something different or because they know me, not just because I'm a banking lawyer.'She adds that people are putting more thought into whom they are inviting to events as the market becomes more competitive.

The Latin American party guest list included HSBC, the European Bank of Reconstruction and Development, BNP Paribas, Deutsche Bank, Banco Nacional De Mexico, and the Brazilian Chamber of Commerce.A recent Denton Wilde Sapte energy department party, which adopted a Cuban theme, was less explicable, leaving Denton's lawyers none the wiser about the choice of theme, but Ms Gardiner is clear about her firm's strategy: it has Latin American offices, a European-based practice group representing foreign investors, and its accountancy parent, PricewaterhouseCoopers, has recently set up a Latin American tax group.But not all law firms have such a focused approach.

Landwell is a young law firm and marketing is important for its business development.

Although some firms leave entertaining to the individual partners, what Ms Gardiner dubs the 'scattering' approach, is becoming less common.There is still a hard core of City firms which play down their marketing and events, though most of the big City firms will have an in-house team to organise their gatherings, realising it is going to take more than a glass of lukewarm Chardonnay and a bowl of peanuts to get their clients to drop by on their way home from work.But they are keen not to be seen to be spending their clients' fees too extravagantly, and would prefer to be known for their seminars than their parties.

A member of the marketing team in one magic circle firm says: 'People tend to err on the side of conservatism.

Banks themselves feel quite comfortable being lavish in their expenditure, but I don't quite get the impression that accountancy and law firms are quite in that league.'Of course, they will push the boat out for a special occasion.

To entertain the mayo r of Chicago on a recent visit, Allen & Overy's well-connected partner Peter Mimpriss organised a reception at St James's Palace for the Civic Trust, of which the Prince of Wales is patron.

And Prince Charles himself was at the reception.It is not just the law firms that are doing the entertaining.

Several banks now have teams dedicated to keeping law firms happy, and other clients are moving in that direction.

The Virgin Group turned the tables when it invited its law firms to celebrate a panel review at Sir Richard Branson's nightclub Heaven, and some journalists to watch.

The experiment was a success, though it might have been different story if the party had been held before the review.Paul Jaffe, who does strategic communications for firms such as Berwin Leighton Paisner and Barlow Lyde & Gilbert, says that apart from big set-piece occasions, many law firms are interested in more specialist events, with particular departments looking for strategic advice on their target market, and to find out what their competitors are doing.

He says: 'Law firms are trying to get more sophisticated, better value for money, and more appropriate hospitality.'He identifies one trend, which has come with the increase of women in the profession, and particularly holding in-house positions where they are responsible for the selection of law firms.

'In the last few years the rise and rise of women has meant less rugby and cricket, and more art galleries and set-piece events.'Ms Gardiner agrees: 'The point about women is important.

Traditionally, you would take people to the football and rugby, and even drinking in pubs is still a man's culture.'Landwell has started taking small groups of women clients to the Sanctuary, a London health club, and is planning to make it a regular occurrence.

'Huge gatherings are that much less efficient.

The smaller ones can be effective, and you can engineer something so that you get two clients together.'This reflects the experience of the American Bar Association's Women Rainmakers Network, which emphasises women using different, more personal techniques, including inviting clients to their home to meet the family and have dinner.Graeme Baird, a partner at Hill Taylor Dickinson, suggests that day events, such as golf may also be going out of fashion because they involve taking a whole day off work.Hammond Suddards Edge showed its softer side this year when it invited its clients to the Chelsea Flower Show, but its communications headMatthew Baldwin pertinently points out this was not exclusively for women.Tapping into health and gardening trends also has the advantage of offering clients something unexpected to attend.

But the women at the London office of US firm Weil Gotshal & Manges say they enjoy football just as much as the men.The firm is mad-keen on sport, and has a big budget for a range of events from motor racing and sailing, to golf and tennis.

The firm's press officer Caroline Knock says structured corporate hospitality is encouraged, but adds that 'clients are relatively cheeky and say: "Can you get me tickets to the cricket?"'.But she denies forking out for tickets to events, such as the Madonna concert held last week at Earls Court, is an extravagance.

She points out that some firms take clients skiing for the weekend.Weil Gotshal also has a season ticket to Arsenal, which if unused by partners and clients, will be offered to journalists and then staff.

'We make sure nothing goes to waste,' explains Ms Knock.Mr Baird also uses his Arsenal season ticket, and the firm organises a whole range of activities for its clients from claypigeon shooting and go-carts to play stations and wine tasting.

The firm does hold an annual set-piece do at Christmas, but Mr Baird says that hospitality does not have to cost much to be effective.

'We hold pop and sports quizzes.

I don't think cost is important.

It's the time you put into it that counts,' he says.Most firms say their bottom line is the budget, but Mr Baird says Hill Taylor Dickinson draws the line at foreign travel - even if the guest flies easyJet to a grand prix, or is treated to something as harmless-looking as a golfing weekend in Ireland.Obviously ensuring the main social events of the year are covered costs money - though for SJ Berwin, for example, with its cricket client base, a box at Lord's is vital for good client relations.

But as long as such perks can be put down to client development or new business, it is unlikely that they will come to an end.As practices continue to tread the fine line between spending their clients' cash and rubbing their noses in it, freebies from sought-after events through to one-to-ones in the sauna will remain the price that law firms must pay to entertain their corporate clients.