Starting work at the age of 14 after his father's business failed, Doubleday began with Charles Scribner's Sons in New York.
The following year, Doubleday and McClure accepted a contract to manage the great publishing house of Harper & Brothers, at the instigation of their banker, J. Pierpont Morgan.
On taking control, Doubleday dug thoroughly through Harper's books and decided that the company's finances were in a shambles; he convinced McClure and Morgan to call off the deal.
On December 31, 1899, growing tension between Doubleday and McClure led the two men to dissolve their partnership.
His personal friends included James Barrie, Andrew Carnegie, Alfred Harcourt, Edward Mandell House, Rudyard Kipling, T. E. Lawrence, Christopher Morley, Mark Twain.
Doubleday married Neltje De Graff (1865-1918) on June 9, 1886, who published several books on gardens and birds.