RICHARD and Judy have done it for years, Michael Parkinson has managed it with his son, and Paula Radcliffe does it every day with her husband - work together, that is.

Even Penny Lancaster is joining the cast of the Rod Stewart musical Tonight's The Night, making her the latest in a long list of showbiz couples whose professional and personal lives have overlapped.

And it's not just celebs. If you're a family-minded person, who better to go to work with than your nearest and dearest?

Working side by side with your spouse means that you really will be sharing everything, for richer and for poorer, for better and for worse.

But before you write your partner's resignation letter for them and set up your dream family business, it's worth thinking about the pressures and problems that working together can bring.

"Working together does put a tremendous strain on any family relationship, especially if you're partners," warns relationships expert Susan Van Scoyoc.

"You have to make sure your relationship comes first, no matter how the business is doing.

"I have seen people who have thrived working with their partners - but you have to think about it before you start."

If you see your spouse at work and at home, it's very difficult to keep a separation between the two - and that can be unhealthy.

"The fact is that people's personal and business lives become intertwined," says Van Scoyoc. "You don't switch off when you get home."

And, according to occupational psychologist Dr Angela Carter, who runs Just Development, a company which specialises in advising people about work issues, frustrations quickly surface if partners react differently to stress.

"Different people have different ways of coping, and women tend to verbalise while men just want to switch off and not want to know any more," she says. "If partners end up in a position in which the only thing they ever talk about is the business, that's a very dangerous place to be."

The answer is to set clear, predetermined limits to conversations about work.

"Set a time limit after which you don't talk about it," advises Van Scoyoc. "I knew one couple who talked about their business so much it had affected everything - so they set a rule of no business in bed."

Very few couples can cope with being together 24-7 - it's suffocating, and everyone needs space to breathe.

"It's important that people who work with family remember that different people take time out differently.

"There does need to be allowance to have time away doing something that's just for you, alone," says Van Scoyoc.

"That's especially important for children working with parents - if you're working with parents full-time you may well not want to go round for dinner.

"It's important to take time out in those circumstances, but also to make sure that social family contact doesn't recede."

Dr Carter says: "Generally, at work there is not an equal power relationship between couples.

"For example, if the man runs the business and his partner is his PA, it's easy to take that balance into your personal relationship. He may carry on treating her in that way at home.

"You need to understand that to stop it from happening."

The problem can be particularly acute when working with your children.

"If a parent isn't careful there's a tendency to treat the child as a parent, rather than as an employer," says Van Scoyoc. "They may tend to be more critical, and praise less.

"Equally, the younger person has to be careful not to take advantage of their position as the boss' child."

It's not all doom and gloom though.

"There are real benefits to working with family," says Carter. "There's an increased speed of communication - the person closest to you knows the context of your life, and understands the issues you face.

"As long as you're careful not to exclude others, you know each other so well it's easy to work together."

And, of course, you get to see your partner virtually all day, every day.

"In many new relationships, couples love to spend all their time together," she says. "If you can keep that going in the work situation, that's a mightily beneficial thing.

"If you're working together to achieve your shared dreams and aims, that brings a lot of positives and happiness to a relationship."

Perhaps the most famous working partnership in showbiz is Richard Madeley and Judy Finnigan.

Married for 18 years, they moved on from This Morning to their own eponymous show on Channel 4.

Richard, 48, has said having Judy, 56, by his side at work is essential to his happiness - but only because they are in love.

"You have to go through a lot and it's only possible if you are with your soulmate."

But working with your partner in the public eye can bring its problems. Immediately after Paula Radcliffe finished a disappointing fourth in the 2001 World Championships in Edmonton, husband and manager Gary Lough inquired why she had not run the tactics they had agreed.

A tearful and very public slanging match on the track followed before the runner stormed off.

She later said: "Immediately afterwards Gary knew it was the wrong thing to say. My point was, you have a right to that opinion, but do it on the warm-up track afterwards."

Psychologist Dr Angela Carter says rows can often help a working relationship: "If something good comes out of the creative tension that has caused the row and a problem is solved, that's a good thing."