“The days when men referred to each other by their surnames, when office hierarchies were minutely calibrated by the use of the prefix ‘Mr’ or ‘Miss’ are long gone.

Informality is the order of the day and first names are de rigueur; even in professional situations, when dealing with doctors, lawyers, policemen, bank managers, informality is being adopted. There is much to be applauded here – empty conventions are alienating and impede communication.

But traditional fail-safes are very useful when you find it difficult to judge the social climate. If in doubt, opt for formality, and beware; older people may find the instant adoption of the first name disconcertingly overfamiliar.”

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