Apart from captaining the "Royal Scotman" for a period, Mary Sue's duties included managing the sprawling empire of the Guardian's Office agency within the Church of Scientology and serving as the chair of an executive group known variously as the Commodore's Staff Aides, the Aides Council, and the International Board of Scientology Organizations. This body was responsible for overseeing each of the seven organizational subdivisions of the Church of Scientology. She played a central role in the financial management of the Church of Scientology's two principal corporations, the Church of Scientology of California and the United Kingdom Church of Scientology. She was a sole signatory to the Church of Scientology's trust accounts and was also a director of the Operation Transport Corporation (OTC), a company established in 1968 that served as a conduit for cash transfers from the Church of Scientology to L. Ron Hubbard personally; it was characterized by US Tax Court as a "sham corporation" whose role was the enrichment of the Hubbards. She personally handled large quantities of cash on Hubbard's behalf. In the summer of 1972, Hubbard ordered that around $2 million in cash be transferred from OTC bank accounts in Switzerland to the "Apollo", where it was stored for the next three years in a locked file cabinet to which Mary Sue Hubbard had the only set of keys. Her salary was relatively modest, amounting to $30,430 ($150,732 in 2007 prices) between 1970 and 1972, though she did also benefit from tens of thousands of dollars a year in living expenses paid for by the Church of Scientology.