The Watch Tower Bible and Tract Society of Pennsylvania is a non-stock, not-for-profit organization headquartered in the New York City, New York borough of Brooklyn. It is the main legal entity used worldwide by Jehovah's Witnesses to direct, administer and develop doctrines for the religion and is often referred to by members of the religion simply as "the Society". It is the parent organization of a number of Watch Tower subsidiaries, including the Watchtower Society of New York and International Bible Students Association. The number of voting shareholders of the corporation is limited to between 300 and 500 "mature, active and faithful" male Jehovah's Witnesses. About 5800 Jehovah's Witnesses provide voluntary unpaid labour, as members of a religious order, in three large Watch Tower Society facilities in New York; nearly 15,000 other members of the order work at the Watch Tower Society's other facilities worldwide.