They used to stage Foreign Office weekends. Groups of young hopefuls went to a country house to 'get to know each other'. And learn things.
And discuss Great Issues. But they knew perfectly well that what really counted in the race for preferment was 'which fork'.
How would a man (there were fewer women in the golden age of the Foreign Office weekends) conduct himself? Would he know what to do? Or what to wear? All these things, so they said, were monitored by seasoned FO men who knew the form. They were looking for what are now called social skills.
Does this person know how to mix with the world's upper middle-classes with confidence? And instinctively know when something is right? As we know now, that approach favoured Southern public schoolboys over Northern chemists from grammar schools - which is not PC, so they've changed it.
Life has moved on, but not as much as you think. The 'social' side of business has actually increased for senior managers because of the new baronies of modern organisations, Human Resources and Corporate Affairs.
HR puts on internal events for management development; Corporate Affairs puts on external events for corporate reputation. It can be a real strain on a wardrobe.
Then, too, (American) HR thinking - 'Let's make this place flatter, more co-operative and thoroughly empowered' - led to dress-down Friday, one of the greatest wardrobe tests of all time. The response to dress-down Friday has been to invent a new uniform, a complete No Surprises, Regular Guy combination of the following fail-safe components: chinos or khakis, polo or button-down shirts, and deck shoes
Chinos and khakis are sort of Home Counties preppie, Anglo-American East Coast off-duty OK. They're cut loose, so they don't look sharp or sexy.
And they're 'trad' - so, no combats (too fashion-conscious and clubby); no jeans (too much of a minefield); and certainly no leathers or anything like that. Ralph Lauren Polo shirts are everywhere on dress-down Fridays, but unbranded is best. Most cautious souls wear pretty conservative colours: navy, grey, brick. Brooks Bros-type button-downs are safer still. Deck shoes imply that you mess about in boats, know where the Hamble is, and understand manly co-operation Again, the look is safe Anglo-American.
Penny loafers have the same acceptable profile, while trainers are still a real issue.
Jackets are a problem for dress-down days. A full-tilt blazer with brass buttons can look overdone; leather jackets look like too much striving after cool. Well-worn linen is one option, but avoid the whole-hog Merchant Ivory look. Another is a variety of cotton and sport-derived things provided they're sober enough, which means no fluorescents or go-fast stripes.
The Establishment American look is the one that everyone feels safe with.
Out-and-out Sloane is a bit of a problem with its class and age overtones.
A tweed jacket may be OK for bonding at a country hotel but it could be OTT in the office. Smart casual is the term. This covers a range of purpose-built clothing but absolutely not wearing your old formal clothes in a casual way - as in formal shirt but no tie, or fashion worn casually.
David Beckham at home certainly isn't it either.
Meet-the-celebs-and-luvvies sponsored events are different again and usually have a form dictated by the event - concerts, charity dinners, drinks parties, tennis and polo, for instance. Have you got your own decent dinner jacket, your own black tie (no pre-tied multicoloured bellboy version)?
The point about black-tie - like everyday office uniform - is detail, quality and accessories. Shoes are a killer detail. You don't just wear your office Oxfords, almost turning up at the toes. On the other hand, getting proper evening shoes is difficult and the wrong patent numbers can look deeply spivvy.
As for the other bits, you could do worse than study that immortal work, The Sloane Ranger Diary 1983 (by Ann Barr and Peter York), which lists a range of events in the British social calendar and identifies the kit for each - men and women, younger and older.
As for dress-down Friday, since you haven't got a Brooks Bros near you, a judicious combination of Ralph Lauren, Gap and M&S will cover most mainstream options. Or send for Johnnie Boden's catalogue; you'll know everything in there is all right because it's all modelled by superior young professionals - just like you.