The guidelines on house-elf welfare were a set of regulations passed by the British Ministry of Magic regarding the treatment of house-elves. Despite their existence at the time, these guidelines were not enforced by the Ministry of Magic by 1996, and therefore many wizarding households such as the Malfoys and the Blacks mistreated their elves. This led wizards such as Albus Dumbledore and Hermione Granger to personally work to improve the lives of these creatures. In particular, Hermione Granger in her later life would contribute to increasing the quality of lives for house-elves in Great Britain through her work for the Department for the Regulation and Control of Magical Creatures, part of which presumably entailed making sure these guidelines were actually enforced.
- J. K. Rowling's official site (Mentioned only)