The Church of Scientology International, Inc. (CSI) is a California 501(c)(3) non-profit corporation. Within the worldwide network of Scientology corporations and entities, CSI is officially referred to as the "mother church" of the Church of Scientology. In a 1993 memorandum by CSI, the following information was provided to the Internal Revenue Service with regards to CSI's role and functions, its personnel and its income: