Over a period of 11 years, from May 31, 1902 until March 31, 1913, HAPAG’s general director, Albert Ballin, kept a hand-written notebook in which he listed the names of guests visiting his city apartment at Hamburg’s Badestraße 23 (beginning in 1902), his country house in Hamfelde near Trittau (as of 1906), and his villa at Hamburg’s Feldbrunnenstraße 58 (as of 1909). He also noted who did not accept his invitations and commented on individual events. The notebook represents a source belonging to the genre of ego-documents and has the character of a guest book, although there are no visitors’ signatures as is usual for guest books. Ballin presumably kept this document, which consists of 158 unpaginated pages and is privately owned today, as a memory aid for his own private use.