Sub-series consists of the personal and business papers of Henry "Harry" Zenas Osborne, Jr. Harry's personal papers include correspondence from his father while he was serving in Congress, from Lilian while she was at Stanford, and from his brothers. Harry's business papers consist of his financial and real estate records and correspondence. They include his leases on various properties, bank statements, and cancelled checks. Any papers pertaining to his career as a civil engineer are found in his work papers. These include correspondence and drawings related to his work as a civil servant for the city of Los Angeles in the 1910s and his later career as an engineer for a private firm. Also included in this series is his correspondence documenting his involvement with professional societies, including the Municipal League, the Architects and Engineers Society of Southern California, and the American Society of Civil Engineers.