In view of the positive significance of agency book - keeping business, in order to give full play to the role of agency book - keeping business, when revising the Accounting Law in 1993, the "agency book - keeping" clause was added. Those units which do not have the conditions to set up an accounting organization or equip with accountants separately are allowed to entrust relevant accounting service organizations to keep books on their behalf, thus establishing for the first time the legal status of China's agency book - keeping business. Agency book - keeping is a kind of civil legal relationship. This relationship is determined by the principal and the agency in the form of a written contract through mutual consultation.