The Guild of Runesmiths is an organisation that most professional Runesmiths join for experience, legality or training in the art of Runesmithing.
To become a member, only a small understanding of the theory behind Runes is necessary. Then a visit to the Guild itself. It's headquarters is in Belden, however there is a Guild building in most cities and some large towns. The joining process is short and concludes with an exam, followed by some practical Runesmithing.