Originally Posted by Sanguis Mortuum
No. The 'rule' is that the socks should match the trousers, but you can wear contrasting bright colours too. They should not normally match the shoes, and you can probably survive without ever wearing a black sock (even if you're wearing black shoes and black trousers, navy socks would probably be better than black, just to add a bit of depth).
Just wondered what sort of bright colours are acceptable...