ASCII Media Works published 25 volumes between April 10, 2004 and August 10, 2011 under their Dengeki Bunko imprint; 22 comprise the main story,[2][3] while the other three are short story collections.[4][5][6] Yen Press has licensed the series in North America and began releasing it under their Yen On imprint in November 2014.[7] A sequel series of light novels titled New Testament: A Certain Magical Index (新約 とある魔術の禁書目録, Shin'yaku Toaru Majutsu no Index) began publication on March 10, 2011[8] and concluded on July 10, 2019 with the publication of its 23rd volume.[9] A third light novel series, serving as the sequel to New Testament: A Certain Magical Index, is expected to begin publication in 2020.