We have ways of making you stay

Compared to military training, headhunters' preparatory techniques are gentle. However, for naive bankers making a first job move, they may come as a surprise.

Nick Kerrison, a consultant at Mantis Partners, a London-based search firm which puts candidates through role plays to prepare them for the experience of resigning, said he acts harshly to show people what they might come up against. He said: "We rip up their letter of resignation and throw it back in their face."

The next step, said Kerrison, is to interrogate candidates on which company they are thinking of moving to and for how much money, facts they are advised not to divulge under any circumstances.

John Jessen at Smith & Jessen, a Frankfurt-based headhunter, said: "The more information a bank has about the alternative position, the harder it will become for a candidate to leave."

Jessen said once they know where a candidate is planning to move to and how much they will be paid, existing employers have valuable bargaining tools. Inevitably, banks' persuasive techniques centre around money. It is not unusual for existing employers to offer top employees salaries and guaranteed bonuses that far outweigh the packages enticing them away.

Nevertheless, it would be wrong to assume money is banks' only method of holding on to disloyal employees. When 13 bankers at Dresdner Kleinwort Wasserstein in Frankfurt resisted attempts by Credit Suisse First Boston to poach them earlier this month, Andrew Pisker, chief executive of DrKW, denied their allegiance had been bought with "cheque book diplomacy".

DrKW declined to comment on precisely how its wavering employees had been persuaded not to defect, but it did involve a personal touch from the big boss Paul Achleitner, chief financial officer at DrKW's parent Allianz and the former head of Goldman Sachs in Germany. However, common practices are to subject staff to a combination of flattery and mild intimidation.

Banks try to spin out the resignation process so that it takes as long as possible, to give employees plenty of opportunities to reverse their decision.

According to Kerrison, it is common for employers to refuse resignations. He said: "The immediate boss will say 'You can't resign to me: we'll fly you to New York to discuss this with the global head of the division'."

Jessen said star performers can expect several such encounters. "We have had situations where employees have sat in a meeting room for 12 hours and met one senior manager after another."

During this period employees will typically be told how wonderful they are and that great things await them if they stay at the bank. At the same time, aspersions are cast about the choice of new employer. Jessen said: "They will bring in other people who have worked with that firm, who will say the division is going nowhere or the new boss is impossible to work with."

A head of capital markets origination at one bank, said tactics are most complex when entire teams threaten to depart. He said: "It's a question of divide and rule: we say to the number two guy that if he leaves, with his boss, he'll still be below his boss, but that if he stays with us we'll promote him to head of the new team."

David Schwartz, a headhunter at Gow and Partners in New York, said psychology is part of a bank's armoury. He said: "There may be an attempt to reinforce the notion that you are part of a family and that leaving is a form of betrayal."

A managing director at a European bank said some companies put employees in a room with a scrambling device that blocks mobile phone calls, to prevent them calling their new employer.

Resisting such pressure can be harder than it seems. In theory, employees can simply hand in their letter of resignation to a human resources executive and walk away at the end of their notice period. In practice, it is difficult to avoid becoming embroiled in discussions of a more personal nature.

Gisli Gudjonnson, a professor at the Institute of Psychiatry in London and specialist in interrogation techniques, said two factors make it difficult to simply walk away: humans are inherently eager to please; and it can be hard to contradict the wishes of someone in authority.

To counteract this tendency towards appeasement, prospective employers do their best to make candidates feel wanted. Future employees are sometimes given mobile phones and asked to call their new employer for pep talks at specified times during the day of their resignation. In other cases, a new line manager will arrange to meet a prospective employee for lunch on the day they resign.

When star performers are felt to be at risk of returning to a former employer, or being poached by an alternative new employer during gardening leave, headhunters said hiring banks have been known to send prospective employees on exotic holidays.

Jessen said: "We have had clients take away a candidate's existing mobile phones and hand them a new phone with a ticket to the Caribbean until everything blows over."

Faced with enemy interrogation, only James Bond could expect similar treatment.