• Contents as of January 29, 2016: Basutoland (Lesotho), 1926-1946
• Cape of Good Hope, 1821-1909
• Gambia, 1828-1945
• Gold Coast, 1846-1939
• Kenya, 1901-1946
• Nigeria, 1862-1945
• Northern Rhodesia, 1924-1948
• Nyasaland, 1904-1938
• Sierra Leone, 1824-1943
• Southern Rhodesia, 1906-1953
• Tanganyika, 1921-1948
• Uganda, 1901-1945
• Zanzibar, 1913-1947.

Digitized copies of some of the standardized annual Blue Books submitted by British colonial administrators in Africa to the British Colonial Office and containing statistics about the colony.
"The Blue Book was a key item of considerable standing in 19th century colonial administration, Colonial Regulations of the time state that: "The Annual Blue Book containing accounts of the Civil Establishment, of the Colonial Revenue and Expenditure and of various statistical particulars etc. must be completed as early as possible after the close of each year. The various returns which it comprises must be filled up with the greatest possible accuracy and the Statistical Tables must be full and complete, blank copies of the book in sheets will be annually transmitted to each Colony from the Colonial Office". The bare statistical material which the Blue Book provided was somewhat daunting, and the annual report was intended to present in a readable form the gist of the information which the book contained. The directions given in the Colonial Regulations referred to above to colonial governors as to the compilation of the annual report were somewhat terse: "The Governor, in transmitting the 'Blue Book' to this Department, must accompany it with a report which should be written on one side of the paper only, exhibiting generally the past and present state of the Colony and its prospects under the several heads specified in the Book ..." Not all governors, however, provided reports of the required standard, In 1887 governors were informed that, whereas hitherto it had been the practice to wait until a sufficient number of reports had been received, to form a volume, it was now proposed to publish reports separately as they arrived, but, it was added, "It has been decided only to publish the more interesting and important Reports, ..because in some cases the Reports contain too little to be worth producing separately". With the quality of the Annual Reports so variable, the more rigorously standardised Blue Books gain an increased significance through their increased level of, though certainly not absolute, reliability. In May, 1904 the Foreign Office decided that something must be done about the annual reports "to put the condition of our Protectorates more clearly before the House and the Public". The Indian "small Blue Book" was examined as a possible model and rejected as too detailed; in any case it was felt that it would "be preferable for our Protectorates, which must before long be handed over to the Colonial Office, to follow Colonial, rather than Indian, models. We have already in working order the annual Blue Book. All we do now is to assimilate our annual reports to the Colonial Report on the Blue Book. The Blue Book remains in manuscript. But the Colonial Office experience is the publication of the report on the Blue Book induces those people who genuinely desire information to go to the Office and consult the manuscript volume which is there open for such inspection. It is this system which we thought of introducing as otherwise we find that the information contained in the Blue Book is not made use of to its fullest extent." The Annual Reports, currently available on microfilm, do assist with the interpretation of the data in the Blue Books; however, data such as income and expenditure can be analysed and comparisons between countries can be made, through use of these books alone. This collection is a digital extraction from our existing microfilm series, Government publications relating to African countries prior to independence."--Collection metadata page.
With a particular focus on the latter nineteenth century and early twentieth century, the focus of these Blue Books is upon economic development; imports, exports and each territory's balance sheets are a recurring theme throughout. Ecclesiastical records, public works and population statistics are also common themes. The enforcement of the Blue Book structure upon various territories has resulted in some degree of standardisation where administrations were compliant. Analysis of the data within these documents and the different emphases as governments changed, reveals patterns of social change during a period for which limited other records are available.