Tags are what WordPress calls keywords. I attach a small number of tags to every post to help people navigate between content with the same keywords. Tags may be people (Robert Buckland, say), organisations (The Howard League, Revolving Doors Agency), themes (women offenders, homelessness) or specific items (heroin, cocaine, ROTL). If you’re looking to research a particular issue, they can be invaluable.
There has been growing media coverage of Payment by Results schemes since the New Year, both here and abroad (particularly the USA, Canada and Australia).