The most dedicated staff within the Church are members of the Sea Organization (or “Sea Org”), a fraternal religious order numbering more than 5,000 internationally. The Sea Org, an unincorporated association with no formal or informal ecclesiastical or secular structure, is a religious fellowship with a unique tradition. It began in 1967 when, after having resigned from all corporate and management positions, L. Ron Hubbard set to sea with a handful of experienced Scientologists to continue his research on advanced levels of auditing. Sea Org members originally lived and worked aboard a small fleet of ships, headed by its flagship, the Apollo.
As the Sea Org grew, it expanded to land bases such as the Advanced Organizations in Los Angeles and Denmark. Today, Sea Org members continue to care for the upper levels of Scientology, and so all church organizations above the level of Class V are staffed by Sea Organization members.