According to holdings at the Library of Congress, the magazine was published as follows:
For the first five issues of the first volume (January–May 1918) its title was The New World.
The complete run of The World Tomorrow from 1918 to 1934 is available as item 23 in the Library of World Peace Studies edited by Warren F. Kuehl. [New York]: Clearwater, 1978–1982. 1242 microfiches. The Library of Congress' holding starts with vol. 1, no. 6 dated June 1918 and ends with vol. 17, no. 15 dated July 26, 1934.