"Runaways" was started in 2002 as part of Marvel Comics' "Tsunami" imprint. After Marvel cancelled the Tsunami imprint in January 2003, the series moved to the "Marvel Age" imprint. Because of this, the individual story arcs for "Runaways" are collected in small, manga-sized trade paperbacks. The hardcover collections are in normal sized books. In September 2004, the series ended at issue #18. Marvel started the series again in February 2005 and it has been published ever since.