This chapter focuses on one crucial site of accounting practice: the multinational professional service firms, and the historical studies that have examined their emergence and development. Firm histories provide some insight into the work of early accountants. One of the most frequently cited pieces of work on the origins of audit - Watts and Zimmerman - puts forward the thesis that audit arose as a solution to the problem created by the separation of ownership and control. The Lancashire cotton mills, the ‘Oldham Limiteds’ of the late nineteenth century, operating on the principle of one shareholder, one vote, had widely dispersed share ownerships, amateur shareholder auditors and intense investor involvement in their governance. Jones shows that from the beginning of the twelve century medieval administrative and accounting systems in Britain drew on a battery of internal control mechanisms, including accountability, supervision and audit. The Westminster-style of administration of public finance was exported to the British colonies.