"We have found evidence of this in every company we have looked at," said Professor Haslam, speaking at the BA Festival of Science in Exeter. "There seems to be an unwritten law that says 'think female, think crisis'. If a company is doing well, then the 'jobs for the boys' rules still apply, but if it is in trouble, no man wants to give the job to their friends it seems, so for many the answer is to get in a woman."