Progressive employers want to understand why people leave their business and what they can reasonably do to prevent similar departures in the future.

One way to do this is to ask everyone who leaves to take part in an exit interview. It might be the most useful hour of human resource management you ever spend.

If possible, exit interviews should be held on the day the employee is leaving. This minimises any awkwardness their honesty might cause.

A good interview will allow you to receive a full and frank opinion on improvements that need to be made for that employee's successor, as well as general opinions on the business and management style.

Some employees will take the opportunity to criticise everything about the business, their colleagues, and possibly you, but a well-structured exit interview will allow you to see through this and focus on the positive lessons to be learned.

Conducting the interview will also signal to your remaining employees that you take personnel issues seriously and want to improve things for everyone.

Exit interviews should remain confidential; otherwise employees who leave in the future might be discouraged from being frank with you. However, if you feel you have learnt something of value and want to make appropriate changes, you should communicate these to your staff as soon as possible. Among other things, this will help to alleviate any feelings of insecurity the departure might have generated in them.