The series comprises work-related letters from publishers, organisations, breeders and private individuals, already filed by Hubbard under subject, and mostly with original headings. The subjects include advertisment, publicity and distribution of the Dog Lover's Library via literature, the media, dog show stands and a travelling van, 1957-1959; proposals for a pocket book of dogs and for further publications relating to specific breeds, 1951-1960; book orders, 1950-1987; dog purchases, 1958-1959; identification and valuation of paintings in Hubbard's possession, 1957; and breed characteristics of Welsh Beagles, 1949.