From Tar Valon Library
Along the Borderlands, keeps are run by two servants, equal in rank, though with different duties, the shambayan and shatayan. the shatayan is in charge of all the other servants (New Spring, Legends version). They rank above the other servants, such that unlike the other servants, it would be an offence to offer one coin for performing their duties (NS, Ch. 22). When Lan visits Kandor just after the Aiel War, it is the shatayan, Mistress Romera, who presents him to Brys. Generally, the influence of a shatayan goes far beyond ordering servants (TPoD, Prologue ) and even a queen would step warily round one, though not an Aes Sedai (NS, Ch. 25).