Here, a leading etiquette expert explains why he finds over-familiar emails so annoying and runs through the pitfalls we should avoid.

Writing in response to a reader's letter, the society magazine's etiquette expert has decreed that considerate guests should always leave by 10pm on a weeknight, 11.15pm at the weekend.

The dance was frowned upon by etiquette experts.

Modern advice columnists and etiquette experts generally advise against having mortgage burning parties attended by anyone other than immediate family.