The Towers are the centers of the use of "laran" and schools for those who are learning to use their "laran". A designated person is always on duty ("in the relays") to exchange news and requests for help telepathically with other Towers. At least once, the Terrans wonder how news travels so fast on Darkover. Towers are, in theory, independent of any caste discrimination or political influence. Each Tower should have a Keeper, a person to direct both Tower policy and the power of the "laran" users when they gather together in rapport to work. The Keeper of Arilinn is considered the second most-powerful person on Darkover, after the Hastur regent.