For the serious family researcher. Newly published, Genealogy Standards, 50th Anniversary Edition. It is produced by the American Board for Certification of Genealogists, but seems a good place to go as it includes sections on

• Standards for Documenting
• Standards for Researching
• Standards for Writing

Under a tenner on Amazon.co.uk

Amazon .co.uk also has a link to the old Millennium edition, which is more expensive and wrongly labelled! Genealogy Standards:  Millennium Edition

A Mocavo article brought this to Cutlock & Co’s attention and is worth reading if the book appeals.

Update, at April 2016. This information, particularly links, needs revising! Mocavo has merged with FindMyPast, so the blog article has gone.