Dune 7 was the working title for Frank Herbert's seventh Dune novel, which was to be the concluding chapter of the entire Dune series. He had hinted that he was planning to end the series; however, the work was never completed because of his untimely death in February 1986.
Hints of the direction he would have taken with Dune 7 are in Heretics of Dune and Chapterhouse: Dune; however, many unanswered questions remain. He did, however, tell author Norman Spinrad that he "'planned to end the series with a novel that would transition to a fictional universe of democratic rule."
In 1997, as they were searching through Herbert's belongings, Brian Herbert and Kevin J. Anderson discovered two 1980s floppy disks, labeled "Dune 7 Notes" and "Dune 7 Outline." Brian explained in an interview that these contained a short one-and-a-half page outline of his father's thoughts on the seventh Dune novel.
Brian and Kevin completed Dune 7 as two separate novels set immediately after Chapterhouse: Dune. They were released in 2006 and 2007, titled Hunters of Dune and Sandworms of Dune, respectively. The books received a mixed critical response.