Last month HR magazine asked readers if they thought age discrimination in the workplace was a serious problem: 29% said yes, 71% said no.

I am not surprised by these findings but I am particularly concerned that this could get worse over the next couple of years as businesses retrench from the recession. 

I think employers will be looking for younger and perhaps, from their point of view, 'less expensive' staff at the cost of experience. And yet during downturns, it is important to get a good mix of the new and the old, the latter providing the continuity and 'resilience exposure' during the 'ups and downs' of the business cycle. In addition, people are more active longer than ever before, with the prediction in the Foresight project on Mental Capital and Wellbeing  that by 2070 there will be over 21 million people over 65 (a doubling from today) and 9.5 million over 80 (triple the number today).

People will both need to work because of the pension crisis but also because they are healthier and need to be more active to minimise the impact of cognitive decline. Most workplaces could benefit from a mixture of ages, gender, race, and disabled, creating the kind of business community who can understand the wide range of consumers, suppliers and potential future product innovations.

This is not only an ethical issue but also a business issue. If we do not get the right mix of people in the workplace, we will not have the kind of experience, the learning from past failures and mistakes, the understanding of 'grey markets' and all the other aspects of aging that can make a tremendous difference to business.

Cary Cooper is professor of organisational psychology and health at Lancaster University Management School