The organisation received the right to regulate medieval plumbers, who were, among other things, responsible for fashioning cisterns, in 1365.
Today, the company is no longer a trade association, instead existing as a charitable institution.
(The company retains a link to plumbing by awarding medals and prizes in the general building industry.)
Its mottoes are Justicia Et Pax, Latin for Justice and Peace, and In God Is All Our Hope.
Court members have included Fiona Woolf and Paul Flatt.