Together with Katayama Tokuma, Tatsuno Kingo and Satachi Shichijiro, one of a group of renowned architectural students at the Imperial College of Engineering, Tokyo, and a protege of British architect Josiah Conder.
Dispatched to London in 1901 by the co-founder of Mitsubishi, Iwasaki Yanosuke, Sone returned to design and supervise construction of the Senshokaku, an elegant two story mansion built on a steep hillside overlooking the Nagasaki shipyards.
Sone's most famous work is the Old University Library Building (1912), still standing on the Keio University main campus at Mita. In collaboration with his architectural office partner, Chujo Siichiro, Sone produced a building in Edwardian neo-gothic style in red brick with white stone dressings. The Old Library has become possibly the most recognized landmark of the university. This late Meiji period structure employed the latest technology of the time, including steel beams and reinforced concrete floor slabs as well as electrical circuits, gas and steam heat.
In the period between the end of the Meiji era and the outbreak of World War II, Sone and Chujo also designed many other buildings for Keio University including the Keio Corporate Administration Building and the First School Building, both still features of the Mita campus.
Sone as superintendent, together with his former university instructor Josiah Conder as architect, was also responsible for many of the famed red-brick Mitsubishi buildings at Marunouchi, Tokyo. The Marunouchi district was designed as a showcase of earthquake resistant buildings and the Mitsubishi zaibatsu went on to construct over twenty such buildings on the site prior to the Great Kantō earthquake of 1923.