The British Business Census of Entrepreneurs 1851-1911 (BBCE) is a major output from the ESRC-supported project ES/M010953: ‘Drivers of Entrepreneurship and Small Businesses’, Principal Investigator Professor Bob Bennett, the authors of this Guide, and other researchers and assistants (as acknowledgement), with additional support from the Leverhulme Trust, and Isaac Newton Trust. The aim of the database is to provide to users an quality-controlled, consistent, and integrated database that is as complete as feasible for all business proprietors in the period 1851-1911 and aligned to modern definitions used up to the 2011 census. This includes as fully as possible all: o Employers (those who employed others), o Sole proprietor own account self-employed (those who employed no-one else), o Directors of corporations (Limited Companies).