Its annual survey of 42,000 managers found, at every rung of the corporate ladder, a 50% increase over the previous year in the number who resigned to seek alternative employment. The institute said companies often had themselves to blame for the exodus. The most common reasons given by executives for handing in their notice was lack of training and job insecurity caused by corporate restructuring.

The institute said 81% of companies were reporting recruitment problems - a fourfold increase since 2002 and the highest figure since the survey began in 1973.

"In a sign that employers are becoming increasingly desperate to find the right calibre of staff; 32.6% now offer golden hellos, compared with just under 16.3% in 2006." More companies, also, offer a finder's bonus to staff identifying appropriate recruits.

But the inducements to recruit newcomers are not supported by effective strategies to retain existing staff. The survey found 7% of managers resigned last year, compared with 4.6% during the previous year.  Employers in the north-west were the most badly affected, with 8.5% of staff resigning in the 12 months to January.

Jo Causon, the institute's director of marketing and corporate affairs, said: "The steep climb in organisations reporting recruitment difficulties, mixed with an increasing number of resignations, should be ringing alarm bells for employers. The marketplace is clearly tipping in favour of the employee. If organisations are serious about retaining the best talent, they urgently need to meet the needs and expectations of their staff."