Gone are the days when workers could be identified by their bowler hats and briefcases. Casual is now the buzzword in many offices. Helen Riley highlights the advantages and pitfalls for purchasers and their suppliers

As a procurement specialist for Rentokil Initial, Neil Dixon divides his working time between days at the office and meetings with suppliers and key contacts around the UK. He is always on the lookout for new contracts and better deals, which means plenty of contact with other professionals in a range of industries.

For Dixon, one of the key rules of business is that first impressions count. So he wouldn't dream of setting off for work in anything less that a smart three-piece suit.

"It's important to look the part and though we don't have an official dress code in my department, people generally look smart," he says. "I favour a classic look and although I often meet suppliers who are more casually dressed, I don't think that would work for me."

Perhaps more than many others in an organisation, purchasing professionals - and their suppliers - are the ones who are likely to be working on deals worth millions of pounds. So for them, needing to create the right impression can literally be a $64,000 question.

Appearances do matter - and that goes for the public sector as well. Elaine Hutchinson, senior purchasing assistant with the Community Health South London NHS Trust, says: "Officewear within the department is fairly flexible, but suits are the order of the day when it comes to meetings. If you look professional, you feel professional."

Both Dixon and Hutchinson recognise the importance of looking the part at work, and the experts agree with them. Look around on a crowded bus, tube or train and you may be forgiven for thinking that anything goes these days when it comes to workwear. Suits and tailored outfits can seem a bit thin on the ground and there is an increasing trend for casual clothing at the office.

But evidence is emerging that allowing your staff to turn up to work in jumpers and chinos or even jeans and T-shirts could be bad for business: employers should be on their guard.

A recent survey into supplier-client relations by Royal Mail Special Delivery discovered that many companies found suppliers who wear casual clothes in meetings off-- putting, which could prove a worrying finding for companies that operate a casual dress policy or "dress-down days". Overall, the survey found that bad business etiquette, including sloppy dressing, costs British businesses L2 billion in lost contracts.

Chris Scarles, managing director of image consultants Colour Me Beautiful, says: "It's very difficult indeed to dress down and look smart at the same time. In business meetings, dressing down doesn't send out the correct message.

"People act more casually and less businesslike if this is how they are dressed and so it doesn't surprise me that companies aren't impressed with relaxed dress codes."

Scarles points to a backlash against dressing down in the US and says his firm is kept very busy advising some of the UK's largest companies how to look smart and businesslike. Studies by the company have consistently shown that what you wear during office hours can be crucial to your chances of successfully negotiating a deal. Colour Me Beautiful experts say 55 per cent of the impact you make on a colleague is down to the way you look.

Although the Royal Mail survey revealed concern over appearance from only one in io companies, in purchasing that could still translate into multi-million pound contract losses if a casually dressed supplier turns up to a vital meeting with a company that operates a strict dress policy.

Managers at CIPS have taken this message on board. So although Friday is dress-- down day at the institute, staff have clear guidelines about what is acceptable.

If they have meetings with external clients on that day, casualness is dropped in favour of smart clothes, while more regular visitors are told about the casual policy in advance of their visit and are given the opportunity to dress-down as well.

Caroline Smith, director of support services for CIPS, was closely involved in establishing the dress down policy, and says it is working well.

"People generally visit us by appointment, so it is easy to let them know what to expect on a Friday. There are no surprises. If our organisation was based in a city centre, with people dropping in unannounced, then we might have a different policy, but so far dress-down days are working for us."

Casual Fridays have been in place at CIPS for more than two years and Smith has noted an effect on working patterns. She says people are likely to take on archiving and administrative tasks on that day, which might otherwise be put off.

"Our one fear about dress-down days was that staff behaviour might become too casual, but that hasn't happened. The changes we have noted have been positive."

CIPS laid down guidelines for staff before implementing dress-down days - and Smith advises all companies to do this to avoid possible conflicts. If managers don't make it clear to staff that "casual" means shirts and slacks rather than ripped jeans and T-shirts, then they only have themselves to blame if the office ends up resembling a sixth-form common room.

Dressing down might be losing ground in the US, but in the UK it is becoming increasingly commonplace and many companies use it as a way to boost staff morale.

Paul Lee, head of purchasing for Legal & General, takes part in dress-down days that help raise money for charity throughout the company with people paying to don casual gear. But, like most people in business, Lee feels there is a line to be drawn when it comes to making deals and meeting people.

"I always wear a suit at meetings and, while I wouldn't pigeon-hole someone who turned up casually dressed, I would be surprised. I couldn't say it would not make any difference to the bigger picture: first impressions count.

Although there is obviously a trend towards casualisation across every aspect of business, people still seem to recognise the need to make an effort for the big occasions."

But what of those people who have to wear a uniform to work? The good news is that the casualisation of workwear is also affecting them, too. Charles Conway of the Company Clothing Advisory Service points to a growth in the casual corporatewear market, while formal corporatewear is static as evidence of this.

"The increasing use and availability of comfort fabrics, along with changing trends towards casualness across many areas of society, will help to drive this trend. This will be welcomed by the increasing number of younger people in more senior positions," he says.

But Conway does agree that companies should still know where to draw the line. "I've just bought my first ever pair of denim jeans. I'm surprised how comfortable they are - but I wouldn't dream of wearing them to the office in a million years."

Checklist

Finding the right fit:

• Choose clothes that are simple and elegant
   
• A suit is always a good choice for men and women. Choose easy-care fabrics in single neutral colours. Save patterns and splashes of colour for blouses or ties
   
• Join in company dress-down days - up to a point. Be sure to stick to the smart end of the smart-casual spectrum and don't even dream of wearing training shoes or sweatshirts to the office
   
• Women should stick to a discreet necklace and elegant watch - leave the dangly earrings and fancy brooches for the weekend
   
• Shoes should be comfortable and clean
   
• Even if your office is resolutely casual, men should keep a tie in their drawer and women should keep a pair of tights handy for emergencies

More than many others in an organisation, purchasers - and their suppliers - are the ones likely to working on deals worth millions of pounds. So for them, making the right impression really is $64,000 question

Helen Riley is a freelance journalist specialising in business issues