This guide is an updated version of Mandy Banton’s indispensable introduction to the records of British government departments responsible for the administration of colonial affairs, and now held in The National Archives of the United Kingdom. It covers the period from about 1801 to 1966. It has been planned as a user-friendly guide concentrating on the organisation of the records, the information they are likely to provide and how to use the contemporary finding aids. It also provides an outline of the expansion of the British empire during the period and discusses the organisation of colonial governments.