Turning an acquaintance into a business associate is hard, but making them a friend is harder.

There are endless reasons why people fail to connect. And just as a marriage can break down, so can the relationship between a client and a supplier. But how do you prevent it from happening?

Psychologists tell us we tend to like people who disclose intimate secrets more than those who don't. Maybe it's a trust thing. If someone's open enough about their penchant for cross-dressing, surely they wouldn't lie about their business plans.

But when someone you've just met starts pouring out their heart to you, it's a different story. Rather than lend a sympathetic ear, you're more likely to change seats on the bus or join another queue at the checkout. You only went out for a pint of milk.

Yet it's also true that people disclose more to those they like. So if the nutter on the bus is a major buyer in your industry it's probably best to smile politely and hear him out. Similarly, people tend to prefer those to whom they have made personal disclosures. So stick with it.

The trick is not to disclose too much too soon or too often. Take internet dating. Research suggests the way internet daters reveal information about themselves provides clues to developing good relationships. It seems self-disclosure in earnest conversations about your deepest hopes and fears is to be avoided. So no initial chat about global warming, quantitative easing or social unrest. Stick to your favourite music, food and books and a relationship will be formed more quickly.

Communicating online gives you more control over the way you present yourself. Webcams excepted, nobody can see the non-verbal communication that a face-to-face conversation reveals. Like your nervous twitch, constant scratching, or lazy eye. (Plenty of time for that over a candlelit dinner.) So it's far easier to construct an online identity with crafted emails and retouched photos.

A study by Gibbs, Ellison and Heino concluded that the best online daters used lots of positive self-disclosure, along with openness about their intent the very opposite of what many people actually do when they are online dating.

The idea that self-disclosure is important in relationships is no surprise. But while it may be easy to understand in principle, the complexity of the process means it's much harder to do in practice. It's best to be open about yourself and honest about your intentions. Don't be afraid to give of yourself. But remember to share in the right way, at the right time.