Long-Running Book Series

There are some book series that just seem to go on forever. They create epic journeys and worlds that feel almost three-dimensional. They take up entire shelves of book cases all by themselves. These are some of the largest and longest running series in the literary world.

In order to count as one of these a series must meet all of the following conditions:

• Published over the course of at least ten years.
• Contain at least ten books.
• An Expanded Universe is not a series, though there may be series long enough to count inside an Expanded Universe.

A subtrope of Print Long-Runners.

A No Recent Examples rule applies to this trope and examples shouldn't be added until 10 years after the series debuted, even if more than ten books are published before that point.

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Examples

Adventure

• Allan Quatermain, 1885 to 1927, 15 books (later pastiches in 2007 and 2003) beginning with King Solomon's Mines
• Arsène Lupin -1905-1979, 25 books
• The Ashes Series - 1983 to 2003 - 35 books.
• Aubrey-Maturin - 1969 to 2004 - 20 books, 1 unfinished.
• The Black Bat, 1939 to present- 800 books and growing
• Bob Morane, 1953 to present- 238 books and counting^note Author Henri Vernes is credited for the first 229 books althought he admited hiring ghostwriters. From 2012 onward, the books are released under "Bob Morane: Les Nouvelles Aventures"
• Buchanan, 1956 to 1986-23 books
• Bulldog Drummond, 1920 to 1983-19 books
• Commander Shaw: 1960-1995, 22 books
• The Charlotte and Thomas Pitt Series: 1979-2016, 32 books
• DeathLands - 1986 to present - 100 books so far.
• The Destroyer - 1971 to present - 149 books.
• Dirk Pitt Adventures by Clive Cussler - 1973 to present - 21 books
• Doc Savage - 1933 to 1949 - 181 books.
• Eagle Series by Simon Scarrow - 2000 to present - 22 books to date.
• Edge, 1972 to 1989-61 books
• The Executioner - 1969 to present - over 670 books and growing.
• The Gunsmith, 1982 to present- 340 books and growing
• Hopalong Cassidy, 1907 to 1952 -32 books (including the four by Louis L'Amour; original author of the series Mulford's books ran from 1907 to 1941; the first short story appeared in a December 1905 issue of Outing magazine))
• Horatio Hornblower, 1937 to 1967, 11 books
• Hugh North: 1930 to 1968, 26 books
• Imager Portfolio series by L.E. Modesitt, Jr. - 2009 to 2019 - 12 books as 2019
• Jack Ryan series by Tom Clancy - 1984 to present - 21 books as of 2021. Outlived Its Creator - Clancy died in 2013 and the series is now continued by other authors.
• James Bond - 1953 to 1965 - 13 books plus short stories by Ian Fleming; dozens more novels published 1967-present by other authors (with John Gardner alone publishing 16 novels between 1981 and 1996).
• Kino's Journey - 2000 to present - 23 books.
• Kydd - 2001 to present - 24 books ^note as of October 2021.
• The Legendary Moonlight Sculptor - 2007 to present - 57 books.
• Log Horizon - 2011 to present - 11 books.
• The Lone Ranger novels - 1936 to 1956 - 18 books.
• Longarm, 1978 to present- 370 books and growing
• Malko Linge: 1965 to 2013 - 200 books
• Matt Helm: 1960 to 1993, 27 books
• Modesty Blaise (in prose): 1965 to 1996 - 13 books
• The Mrs. Pollifax series by Dorothy Gilman - 1966 to 2000 - 14 books
• Nick Carter: 1964 to 1990-260 books, with earlier series running from 1886 to 1936
• Parker by Richard Stark: 1962 to 2008, 25 books, including the otherwise unpublished novel Child Heist contained in Jimmy the Kid; four Alan Grofield spin-off novels, and one isochronal appearance in Dead Skip by Joes, featuring an untold incident during the events of The Hunter.
• OSS 117 (Hubert Bonnisseur de la Bath), 1949 to 1992 - 256 books
• Quiller: 1965 to 1996: 19 books
• Patrick McLanahan series by Dale Brown - 1987 to present - 20 books by Brown himself, not counting spinoffs, related or Canon Welded titles and collaborations
• Rick Brant series by John Blaine - 1947 to 1968 with an additional book published 1990. 25 books.
• The Sacketts saga by Louis L'Amour goes on for seventeen books, published 1960 to 1985, plus two short stories.
• The Saint: 1928 to 1983 - 52 books, all written by Leslie Charteris between 1928 and the late 1950s, and then either co-written or edited by Charteris from the early 1960s to 1983. Does not include several dozen additional books written in French by other authors in the 1940s and 50s.
• The Sam Durell books, known as the Assignment series - 1955 to 1976 for 42 books by the original author, Edward S. Aarons, then continued until 1983, supposedly by Edward's brother but actually a ghost writer, for another 6 books, bringing the total to 48.
• The Scarlet Pimpernel, 1905 to 1936, roughly 18 books (author Orczy would also make references to the Pimpernel in her other works; later pastiche novels by C. Guy Clayton and Lauren Willig)
• The Shadow, 1931 to 1980, 335 novels and two short stories, with a film novelization in 1994 by Luceno and a cameo in the novel The Purple Zombie (featuring the Avenger)
• Sharpe, 1981 to 2006, 21 novels and three short stories.
• The Spider, 1933 to 1943, 118 novels, with a short story anthology from Moonstone in 2007 and two pending novels in 2012
• Slocum, 1975 to present-380 books and growing
• Tarzan by Edgar Rice Burroughs - 1912 to 1965 - 24 books in the main series, plus two children's books and four authorized or co-authored novels. Maude Robinson Toombs' novelization of the Elmo Lincoln serial. Reboot series commenced by Andy Briggs in 2011. Robin Maxwell novel due in 2012. Authorized Tarzan short stories in Worlds of Edgar Rice Burroughs anthology by Baen, unauthorized tales in Under the Moons of Mars anthology.
• The Trailsman, 1980 to 2014 - 396 books.
• Zorro series - 1919 to 1947, plus spin-offs - 11 or more books and volumes of short stories (original novels/stories by Johnston McCulley; later novels edited by Greg Cox in 1990's, also later novels by Jan Adkins and Isabelle Allende in 2005; Moonstone's Tales of Zorro and More Tales of Zorro published even later)

Children and Young Adult

• The Adventure series of children's novels by Willard Price - 1949 to 1980 - 14 books.
• Alex Rider - 2000 to present - 12 books, including one prequel and a book of short stories which are included in the series' numbering^note Author Anthony Horowitz intended the ninth book in the series, Scorpia Rising (published 2011), to be the last book in the series. However, he had a change of heart whilst working on the book of short stories and revived the series in 2017
• Amber Brown - 12 books and 6 A is for Amber books.
• Amelia's Notebook - 1995 to 2015 - 34 books.
• American Girls Collection - 1986 to present - 70+ books, including spinoffs and additional published series
• Angelina Ballerina - 1983-present; 60 books (the original series is 17 books, along with various animated series spinoffs), with books being reprinted as of 2022.
• Arthur - 1976 to 2011 - At least 26 books in the main Arthur Adventure series. At least a dozen D.W. books. 29 chapter books based on television episodes and seven "Good Sports" chapter books. At least 25 other spinoff and activity books.
• Babar - 1931 - current - 7 books by original author Jean de Brunhoff, over 60 by Laurent de Brunhoff.
• The Baby-Sitters Club - 1986 to 1999 - 131 books plus spin-offs, and revived in the late 2010s with reprints and a series of graphic novels.
  • Baby-Sitters Little Sister - 1998 to 2000 - 122 books, and like its parent series, revived with reprints and a series of graphic novels.
• Betsy-Tacy - 1940 to 1955 - 10 books (plus three related books not part of the main series)
• The Black Stallion - 1941 to 1983 - 20 books. (Not counting sequels written by the original author's son.)
• The Bobbsey Twins - 1904 to 1979 - 72 books (plus an additional series of 30 books published between 1987 and 1992)
• The Boxcar Children - 1923 to present - 152 main-series (as of 2019) and 30 spinoff books (including a cookbook).
• Bugs - 1988 to 2016 - 26 books
• Cairo Jim - 1991 to 2007 - 20 books
• Cam Jansen - 1980 to present - 35 books in the main series, plus another 15 in the Young Cam Jansen series.
• The Camp Half-Blood Series - 2005 to present - 15 books plus 5 companion entries. The 'Verse also includes The Kane Chronicles and Magnus Chase and the Gods of Asgard, each having three books and their own companion entries and focusing on different mythologies but written by the same author.
• Chalet School - 1926 to 1970 - 58 books
• Choose Your Own Adventure - 1979 to 1998 - 185 books.
• Clifford the Big Red Dog - 1963 to present - 75 books.
• Deltora Quest - 2000 to 2016 - 25 books (15 books in the original three series, 3 books in The Three Doors spin-off/sequel series, 4 books in the second spin-off/sequel series Star of Deltora, 3 spin-off companion guides)
• Diary of a Wimpy Kid - 2007 to present - 18 books (if the original webcomic is included, the series started in 2003).
• Dorrie the Little Witch - 1962 to 1992 - 20 books.
• Dragon Slayers' Academy - 1997 to 2012 - 20 books.
• Ella and Friends - 1995 to present, 31 books
• Encyclopedia Brown - 1963 to 2012 - 28 books
• Endless Quest - 1982 to 1996 - 51 books.
• Fear Street - 1989 to present - 123 books
• Franklin the Turtle - 1986 to 2002 - 27 books.
• Freddy the Pig - 1927 to 1958 - 25 books and one collection of poetry.
• Geronimo Stilton - 1997 to present - 82 main books so far, plus multiple specials and spin-off series.
• Goosebumps - 1992 to present - 137 books, plus various spinoffs such as Give Yourself Goosebumps
• The Hardy Boys - 1927 to 2005 - 190 books plus spin-offs. A new series, Hardy Boys: Undercover Brothers, considered a reboot and continuation of the canon, began immediately after and continues to the present.
• Horrible Harry - 1988 to 2019 - 37 main books plus 4 spin-off books.
• Horrid Henry - 1994 to present - 20 books with a 21st coming soon.
• The House of Night - 2007 to 2020 - 16 novels (12 in the original series and 4 in the sequel series) and 4 prequel novellas, bringing the total number to 20 books. The total goes up to 23 if you count the companion guides and comic book miniseries (the latter is often published in a single volume).
• How to Train Your Dragon - 2003 to present, 12 main books, 2 World Book Day books, and 2 extra books (a guide and a journal).
• The Incredible Worlds Of Wally Mc Doogle - 1993 to 2007 - 28 books.
• Jennings - 1950 to 1977 - 25 books.
• Junie B. Jones - 1992 to 2013 - 17 in original series, 11 in Junie B., First Grader, 2 supplementary books
• Kaiketsu Zorori - 1987 to present - 72 books.
• Level 4 - 1994 to 2007 - 13 books.
• A Little Bush Maid (aka the Billabong series) - 1910 to 1942 - 15 novels.
• Little Critter - 1975 to present
• Little Golden Books - Well over a hundred books in the series have been released, on regular intervals since 1942.
• The Magic Treehouse - 1992 to present - 60 books, plus 34 "fact tracker"/"research guide" spin-off books
• Maisy - 1990s - current - numerous, at least in the 40s
• Max and Ruby - 1979 to present - 44 books
• Mercy Thompson - 2006 to present - 12 books in the main series, a spin-off book series that has 5 books, as well as varous short stories.
• The Mortal Instruments - 2007 to present - 15 books, 6 more in the making, 3 spin off series with 10 short stories a piece, and 3 companion books.
• Nancy Drew Mystery Stories - 1930 to 2004 - 175 books plus spin-offs. A new series, Nancy Drew: Girl Detective, considered a reboot and continuation of the canon, began immediately after and continues to the present.
• Papelucho - 1947 to 1974 - 12 books.
• Professor Branestawm - 1933 to 1983 - 13 books.
• Raggedy Ann - 1918 to 1977 - 44 books.
• The Railway Series, 1945 to present - 42 books as of 2011. First 26 by original author Reverend Wilbert Awdry, others by his son Christopher.
• Noddy - 1949 to 1963^note All written by Enid Blyton before her death in 1968 - 24 books ^note  The 25th book was released in 2009 by the author's granddaughter. , numerous books written after Blyton's death in 1968.
• Rainbow Magic - 2003 to present - ongoing, with over 240 books in total.^note Counting both books released in the UK and exclusives to the US, as well as books that have yet to come out but have been confirmed, this consists of (as of April 2017) 182 main series books, 51 special editions and 10 stand-alone one-off stories, making 243 individual books in total. On top of that there's also a direct-to-DVD Japanese co-production animated movie that released in 2010, though that isn't counted among the number because it isn't a book.
• Ready, Freddy! - 2004 to present - ongoing, 42 books so far
• Redwall - 1986 to 2011 - 22 books.
• Ricky Rapper - 1997 to present, 20 books
• Sammy Keyes - 1989 to present - 16 books so far.
• The Secrets of Droon - 1999 to 2010 - 44 books.
• Spot the Dog - 1980 to present - Uncertain number of books, but likely 100s, including spin-offs
• Strega Nona - 1975 to 2017 - 13 books.
• Sweet Valley High - 1983 to 2003 - 152 books plus-spin offs, some of which are large enough to count themselves.
  • Sweet Valley Twins - 1986 to 1998 - 188 books plus spin-offs. Recently revived with a graphic novel series.
• Tantei Team KZ Jiken Note - 2011 to present - 35 books as of March 2021, plus 10 spin-offs.
• Tatu and Patu - 1999 to present, 23 books including the original Veera books.
• The Three Investigators — Original series: 1964 - 1987, 43 books. Crimebusters revamp 1989 - 1991: 11 books. Overseas versions have added more; the German series has more than 150 titles, still going on.
• TKKG - 1978 to present - 167 books.
• Tom Swift - Original series: 40 books, second series: 34 books, third series: 11 books, fourth series: 13 books, fifth series : 6 books
• Trixie Belden - 1948 - 1986 - 39 books.
• The Vampire Diaries - 1991 - 2014 - 13 books...depending on which continuity you go with. After being fired from the series after the seventh book, L. J. Smith wrote two fanfictions continuing the series as she wanted to write it, released in 2013 and 2014. There is also a 6 book spin-off series, Stefan's Diaries, although they're set in the TV show's continuity and aren't considered canon within the book series (not to mention occasionally contradicting the show itself).
• Warrior Cats - 2003 to present - 40 main books, 18 novellas, 14 manga volumes, 13 "super editions", 5 other spin-off books, still ongoing.
• Wings of Fire - 2012 to present - 15 main books over three five-book arcs, 4 “Winglet” short stories, 6 graphic novel adaptations with a seventh announced, 2 “Legends” spinoffs, a coloring book and drawing guide, and an upcoming lore guide. Still ongoing.

Fantasy

• Baccano! - 2003 to present - 21 volumes
• The Black Company - 1984 to 2019 - 11 books, 6 short stories, and several omnibus editions.
• Casca: The Eternal Mercenary - 1979 to present, at least 37 volumes.
• A Certain Magical Index - 2004 to present - 22 volumes in the first series, 23 in the second series, a third series planned, plus several side story volumes, and that's not even counting the spinoff manga.
• Chivalry of a Failed Knight - 2013 to 2023 - 19 volumes.
• The Chronicles of Thomas Covenant - 1977 to 2013, with only 10 novels and one novella (the novella Gilden Fire was originally released in 1984's Daughter of Regals and Other Tales).
• Circleverse: 1999 to present, 11 books.
• Conan the Barbarian - 1932 to 2003, (All but one published long after author's death in 1936) - 60+ books^note The actual number is currently unknown; due to the differences in copyright-laws between countries (or even within the USA at different times), many books considered licensed in one country are considered bootlegged elsewhere. An entire series of over forty novels for instance was published in Russia throughout the 1990's, but has never seen the light of day anywhere else.
• Deryni - 1970 to present - 15 novels (with a 16th in process as of 2011), four volumes of short stories, essays and other supplementary material.
• Deverry - 1986 to present - 16 novels.
• Discworld - 1983 to 2015 - 41 novels, at least 6 short stories, plus various companion books and guides.
• Dragaera - 1983 to present - 12 of 19 planned Vlad Taltos books, 3 Khaavren Romances (1 in 3 volumes), one standalone novel, plus short stories.
• Dragonlance Chronicles - 1984 to present - 11 books.
• Drenai Saga - 1984 to 2004 - 11 books.
• The Dresden Files - 2000 to present - 17 books of 23 planned^note give or take a few, "depending on whether [his] kid is serious about going to grad school...", plus two short story collections, eight graphic novels, and two RPG guidebooks.
• Durarara!! - 2004 to present - 13 volumes in the original series, plus a sequel series (Durarara!! SH) which began in 2014 and is ongoing.
• The Elric Saga - 1972-2005, 11 books
• The Familiar of Zero - 2004 to 2017 - 22 volumes, plus a side story collection.
• Garrett, P.I. - 1987 to present - 13 books
  • Sweet Silver Blues
  • Bitter Gold Hearts
  • Cold Copper Tears
  • Old Tin Sorrows
  • Dread Brass Shadows
  • Red Iron Nights
• Gleams of Aeterna - 2004 to 2019 - 15 volumes, plus a novella collection.
• Gonna Be the Twin-Tail!! - 2012 to 2022 - 22 volumes.
• Gor - 1966 - present - 33 books plus one collection of short stories.
• Gotrek & Felix - 1999 to present (although the first book was merely a collection of short stories from the late 80s/early 90s) - 12 main books, an audiobook, numerous short stories and two spin-off series.
• Grimgar of Fantasy and Ash - 2013 to present - 19 volumes, plus two volumes of side stories.
• Guin Saga - 1979 to 2009 - 126 volumes, plus 21 side-stories.
• Harem in the Labyrinth of Another World - 2012 to present - 12 volumes.^note The original Web Serial Novel was serialized from 2011 to 2019, but the published version has continued on for longer.
• Heralds of Valdemar - 1987 to present - 34 books.
• The Heroic Legend of Arslan - 1986 to 2017 - 16 novels, plus one side-story
• Horizon in the Middle of Nowhere - 2008 to 2018 - 29 volumes.
• Immortals After Dark - 2006 to present - 14 books in the main series, a spin-off consisting of 2 books and 2 novellas.
• InCryptid - 2012 to present - 11 novels and counting, plus 49 short stories/novellas and counting (published in various anthologies, on the author's website, and on Patreon)
• INVADERS of the ROKUJYOUMA!? - 2009 to present - 38 volumes, plus spin-offs, and Drama CDs.
• Is It Wrong to Try to Pick Up Girls in a Dungeon? - 2013 to present - 19 volumes, plus the side series Sword Oratoria which has 14 volumes.
• Isekai Cheat Magician - 2013 to present - 15 volumes.
• Kyo Kara Maoh! - 2000 to present - 22 volumes.
• Land of Oz - 1901 to 1920 - 14 books by the original author and a volume of short stories. 1921 to 1963 - 26 books via expansion. This series also has a large number of Expanded Universe titles as the books continue to be added to the public domain.
• The Legend of Drizzt - 1988 to 2016 - 30 books, 2 spin-offs and a handful of comics.
• The Legend of the Legendary Heroes - 2002 to present - 26 volumes in the main series as of 2014, 19 volumes in the side series.
• Lone Wolf - 1984 to 1997, 2010 to present - 28 books, 32 planned.
• Maburaho - 2000 to 2011 - 30 volumes.
• Magical Girl Raising Project - 2012 to present - 15 volumes.
• Malazan Book of the Fallen - 1999 to 2011 - ten books (and each of them a Doorstopper to the point of some translations splitting given books into two separate titles) plus novellas, plus spinoffs.
• Moribito - 1996 to 2018 - 10 books, 3 spin-offs, 1 guidebook, and 1 cookbook.
• Mirage of Blaze - 1990 to 2007 - 42 volumes.
• Myth Adventures - 1978 to present - 19 books.
• No Game No Life - 2012 to present - 11 volumes.
• Novoland - 2005 to present - 46 books (plus eight television series and one film).
• October Daye - 2009 to present - 15 novels, 1 novella, 50 short stories (published in various anthologies, on the author's website, and on Patreon)
• Outlander - 1991 to present; 9 books out of a planned 10 have been published, along with 3 novellas, 2 short stories, 2 companion guides and a spin-off series, Lord John, which includes 3 novels and 6 novellas.
• Realm of the Elderlings - 1995 to 2017 - 16 books and a number of side-stories.
• Re:Zero - 2014 to present - 36 volumes, plus 5 side stories and 9 short story collections.
• The Riftwar Cycle - 1982 to 2013 - 30 books.
• The Rising of the Shield Hero - 2013 to present - 22 volumes.
• Rune Soldier Louie - 1997 to 2012 - 21 volumes.
• Saga of Recluce - 1991 to present - 21 books with another slated for 2021
• The Saga of Tanya the Evil - 2013 to present - 14 volumes.
• Shakugan no Shana - 2002 to 2012 - 26 volumes.
• Shannara - 1977 to 2020- 29 to 32 novels ¹Depending on if a reader counts The Word and the Void in the total. Author Terry Brooks does not, but the events are canonical to the Shannara universe. one graphic novel, one novella, and four short stories. There is also a tv series, Shannara Chronicles.
• Shōnen Onmyōji - 2001 to present - 47 volumes.
• Skulduggery Pleasant - 2007 to present - 11 novels, plus one spin-off and numerous short stories.
• Slayers - 1989 to present - 17 volumes.
• A Song of Ice and Fire: 1996 to present - 5 main books (of 7 planned) totaling nearly five thousand pages (of eight thousand planned), 3 prequel novellas totaling three hundred and sixty pages, 2 (very long) in-universe histories (of 3 planned) totaling eleven hundred pages.^note Technically speaking, there were six novellas, but three of them were never released standalone until they were included as part of Fire and Blood, one of the aforementioned histories.
• Spice and Wolf - 2006 to present - 24 volumes.
• Sword of Truth - 1994 to 2007 - 11 main books, plus 2 side-stories.
• Thieves' World - 1979 to 2004 - 14 anthologies, plus a handful of spin-off novels.
• Tokyo Ravens - 2010 to present - 16 volumes, plus four volumes of side stories.
• The Tortall Universe. The first book was published in 1984, is still ongoing, and now made up of 21 books- and that's not counting the short stories.
• TSUKIMICHI -Moonlit Fantasy- - 2013 to present - 18 volumes.
• The Twelve Kingdoms - 1991 to present - 17 books, plus 1 short story published as an extra of the audio drama adaptation of The Vast Spread of the Seas.
• The Wheel of Time - 1990 to 2013 - 14 books.
• Xanth - 1977 to present - 39 books out of (at least) 54, which is rather a large number for a trilogy.
• Young Wizards - 1983 to present, featuring ten books so far (the tenth was published on February 2, 2016), a collection of three novellas, and at least two short stories.

General Fiction

• Absolute Duo - 2012 to present - 11 books.
• Adachi and Shimamura - 2012 to present - 11 books.
• Aria the Scarlet Ammo - 2008 to present - 37 books.
• Bakemonogatari - 2005 to 2021 - 28 books.
• Boogiepop Series - 1998 to present - 23 books.
• A Dance to the Music of Time - 1951 to 1975 - 12 books.
• Fujimi Orchestra - 1994 to present, 54 books.
• Just William series - 1921 to 1970 - 38 books plus short stories.
• Maria Watches Over Us - 1998 to 2012 - 39 books.
• My Youth Romantic Comedy Is Wrong, as I Expected - 2011 to 2021 - 14 books, plus 4 short story collections.
• Ōkami-san - 2006 to 2017 - 13 books.
• Oreimo - 2008 to 2021 - 17 books.
• Oreshura - 2011 to 2022 - 18 books.
• The Poldark series - 1945 to 2002 - 12 books
• Several of P. G. Wodehouse's series:
  • Jeeves and Wooster - 1917 to 1974 - 18 books.
  • Blandings Castle - 1915 to 1977 - 11 books, nine short stories.

Horror

• Anita Blake - 1993 to present - 20 books.
• Fantômas, 1911 to 1947, 40 books by original co-authors; later books by David White (Fantômas in America, 2007) and adaptations of two plays, Sherlock Holmes vs. Fantômas and Nick Carter vs. Fantômas.
• Fu Manchu, 1912 to 1959, 15 books by Sax Rohmer; later novels by Kay Van Ash and later Bill Maynard in 2009; Terror of Fu Manchu with Destiny of Fu Manchu pending
• The Sookie Stackhouse Mysteries by Charlaine Harris - 2001 to 2013 - 14 books, 1 novella, 16 short stories.
• The Vampire Chronicles - 1976 to 2014 - 11 books.
• Vampire Hunter D - 1983 to present - 35 novels, plus 2 prequel novels, 1 spinoff novel, 1 novella, and several short stories.
• Vampire The Masquerade Novels - Dozens of novels set in the World of Darkness.

Humor

• Dortmunder - 1970 to 2009 - 14 novels and 11 short stories.
• Uncle John's Bathroom Reader - 1988 to present - 29 books (just the main series, topic-specific spinoffs run the total up to at least one hundred).

Mystery

• 87th Precinct by Ed McBain - 1956 to 2005 - 54 novels, plus short stories.
• Adam Dalgliesh by P D James – 1963 to 2008 – 14 novels, plus short stories and cameo appearances in two other novels
• Alex Cross by James Patterson - 1993 to present - 21 books (as of 2013) and 3 movies (as of 2012).
• The Alphabet Mysteries by Sue Grafton - 1982 to 2017 - 25 books.
• Armand Gamache by Louise Penny - 2005 to present - 13 books.
• Aunt Dimity by Nancy Atherton - 1992 to present - 19 books.
• Bernie Rhodenbarr by Lawrence Block - 1977 to present - 11 books (as of 2013).
• Bony by Arthur Upfield - 1929 to 1966 - 29 novels
• Brother Cadfael by Ellis Peters - 1977 to 1994 - 20 novels, three short stories.
• Sharyn McCrumb's Ballad novels - 1990 to present - 11 novels.
• The Cat Who... Series by Lilian Jackson Braun - 1966 to 2007 - 34 books.
• The Charlie Parker Series by John Connolly - 1999 to present, 12 book and one novella (plus one other novel in the same universe).

• David Audley spy thrillers by Anthony Price - 1970 to 1989 - 19 books.

• DeCock by A.C. Baantjer - 1964 to 2008 - 70 books (Dutch).
• Dortmunder by Donald Westlake - 1970 to 2009 - 14 books, 11 short stories.
• Erast Fandorin by Boris Akunin - 1998 to 2018 - 15 books (twelve full-size novels, two novella bundles, and one short story collection).
• Fletch by Gregory Mcdonald - 1974 to 1994 - 11 books
• Gervase Fen by Edmund Crispin - 1944 to 1979 - 9 books, 2 books of short stories.
• Goldy Schulz by Diane Mott Davidson - 1992 to present - 15 books.
• Hamish Macbeth by M.C. Beaton - 1999 to present - 27 books.
• Hercule Poirot by Agatha Christie - 1920 to 1972 - 38 books plus stories.
• In Death - 1995 to present - 52 books in this mystery/sf series.
• Jack Reacher - 1997 to present - 26 books, plus a short story collection.
• John Putnam Thatcher by Emma Lathen - 1961 to 1997 - 24 books.
• Kate Shugak - 1992 to present - 23 novels and 7 short stories.
• Kay Scarpetta series by Patricia Cornwell - 1989 to present - 27 novels and 1 novella; there are also 9 omnibus collections and a Spin-Off Cookbook.
• Lord Peter Wimsey - 1923 to 1939 - 11 books, a play and several collections of short stories by Dorothy L. Sayers, plus three sequels (1998 to 2010) by Jill Paton Walsh based on material left behind by Sayers.
• Marcus Didius Falco - 1989 to present - 20 books.
• Meg Langslow Mysteries - 1999 to present - 14 books plus short stories.
• Midnight Louie - 1992 to present - 20 books plus short stories.
• Miss Marple by Agatha Christie - 1930 to 1971 - 12 books plus stories.
• Nero Wolfe - 1934 to 1985 - 47 books plus short stories.
• Nestor Burma - 1943 to 1985 - 29 novels and 7 novellas.
• The No. 1 Ladies' Detective Agency - 1998 to present - 22 books.
• Perry Mason - 1933 to 1972 - 82 books.
• Phryne Fisher - 1989 to present - 19 books and a short story collection
• Psychic Detective Yakumo - 2004 to 2020 - 12 books, plus several spinoff novels.
• Rabbi Small by Harry Kemelman - 1964 to 1996 - 12 books.
• Rebus by Ian Rankin - 1987 to present - 18 books.
• Regan Reilly Mysteries by Carol Higgins Clark - 1992 to 2012 -19 books, 4 of which were co-authored with Carol Higgins Clark's mother Mary Higgins Clark (there's also an unreleased 20th book)
• Roma Sub Rosa by Steven Saylor - 1991 to present - 11 novels, 2 short story collections.
• Sano Ichiro by Laura Joh Rowland - 1994 to 2014 - 18 books.
• Sister Fidelma by Peter Tremayne - 1994 to present - 21 novels, 2 short-story collections
• Spenser by Robert B. Parker - 1973 to 2011 - 39 books plus a YA "Young Spenser" prequel.
• The SPQR series by John Maddox Roberts - 1990 to present - 13 books and 8 short stories.
• Stephanie Plum by Janet Evanovich - 1994 to present - 30 books, four novellas.
• Tea Shop Mysteries by Laura Childs - 2001 to present - 25 books and counting.
• Tony Hill and Carol Jordan: 23 years and 11 books (not including short stories).
• Travis McGee by John D. MacDonald - 1964 to 1984 - 21 books
• Vatican Miracle Examiner - 2007 to present - 13 books.
• Vera Stanhope by Ann Cleeves - 1999 to 2022 - 10 books (adapted into the TV series Vera, which is also a long-runner)

Science Fiction

• 1632 (by Eric Flint) - 2000 to present - 26 books in the series along with over 60 issues of the Grantville Gazette totaling over 7 million words in print.
• Accel World - 2009 to present - 26 books.
• Aeon 14 (created by M.D. Cooper) - 2012 to present - The main Tanis Richards series has 3 books in The Intrepid Saga, 13 books in The Orion War, and two at time of writing in The Ascension War with more coming. Add in the Shared Universe and the total easily tops fifty.
• Alliance/Union (by C. J. Cherryh) - 1980 to present - 11 books in the main series, plus about twenty more set in the same universe.
• Buck Rogers - 1928 to 1995-13 books, including Armageddon 2419 A.D.
• Cat Planet Cuties - 2003 to 2015 - 20 books.
• La Compagnie des Glaces by French novelist Georges-Jean Arnaud – 1980 to 2005: 98 novels
• Darkover (by Marion Zimmer Bradley and Friends) - 1958 to present - 29 novels, 12 short story anthologies
• Destroyermen - 2008 to 2020 - 15 books.
• The Diadem Saga - 1977 to 1996, with nine books in the main Aleytys series plus two add-on trilogies and a pair of standalone books.
• Dragonriders of Pern - 1968 to present - 24 books.
• Dray Prescot by Alan Burt Akers - 1972 to 1998 - 53 books.
• Foreigner (1994) (by C. J. Cherryh) - to present - 22 books.
• Full Metal Panic! - 1998 to 2011 - 23 books.
• Heavy Object - 2009 to 2021 - 20 books.
• Isaac Asimov:
  • Robot Series: His first "robots" story was "Robbie", from 1940. Dr Asimov started publishing collections of his short stories in 1950, as well as publishing novels in that setting, totaling eleven before author's death in 1992. However, he and his estate have been authorizing dozens of books since the late 1980s, allowing many authors to continue expanding the scope of the series, and Dr Asimov tied together several characters/plots, making The Empire Novels and Foundation Series part of the same continuity.
  • Foundation Series: Begun by Isaac Asimov, and continued by other authors, the Foundation saga itself technically began in 1942 with "The Encyclopedists", but the first novelization was in Foundation (1951). The tenth book released is Foundations Triumph, by David Brin, in 1999. In addition, Dr Asimov wrote Sequels to The Foundation Trilogy that would tie in other stories, including his Robot Series and The Empire Novels.
• Gaunt's Ghosts - 1999 to present - 13 novels plus a few spin-offs and a background book.
• Gor - 1966 - present - 33 books plus one collection of short stories.
• The Great SF Stories - 1979 to 1992 - 25 volumes of short fiction published between the years of 1939 to 1963 (plus one additional volume published in 2001, covering 1964).
• Haruhi Suzumiya - 2003 to present, 12 books plus a spinoff alternate universe manga.
• The History of the Galaxy - 1997 to present - over 30 novels and 20 short stories and counting.
• Honor Harrington - 1992 to present - 14 books in the main series, 10 spin-off books in three separate sub-series, 6 short story anthologies, 3 Young Adult novels, 5 graphic novels, 2 different series of source books, and a first universe compendium with 2 more awaiting publication.
• Horseclans - 1975 to 1988 - 18 novels.
• Horus Heresy - 2006 to present - 38 novels, 103 short stories and novellas (some of which are collated in 21 anthologies), 47 audio dramas (plus 4 audio drama anthologies), 2 artbooks, 2 scriptbooks, 1 graphic novel. Contains two sub-series: The Primarchs (another 15 novels, 7 short stories, and 4 audio dramas) focusing on the leaders of the Space Marine Legions, and The Solar War (1 of a planned 8 novels, plus an unspecified number of planned novellas) a continuation/rebranding intended as a capstone to end the series. Not including the tabletop wargame and associated works (sometimes referred to as 30k), the 2 stand-alone tabletop miniature games, any novels set in the 40k timeline that function as a Distant Sequel to individual stories, or any products branded as or set during the Horus Heresy era that pre-date the series.
• Humanx Commonwealth - 1972 to 2017 - 29 novels plus short fiction.
• In Death - 1995 to present - 52 books in this mystery/sf series.
• Knight's & Magic - 2010 to present - 11 books.
• Legacy of the Aldenata - 2000 to present - 12 books.
• Liaden Universe - 1988 to present - 19 novels plus short stories and counting.
• The Lost Fleet - 2006 to present - 18 books (split between the main series - 6 books, Beyond the Frontier sequel series - 5 books, The Lost Stars spin-off series - 4 books, and The Genesis Fleet prequel trilogy), and 2 short stories
• Mushi-Uta - 2003 to 2014 - 16 books.
• Perry Rhodan - 1961 to present - 39 cycles made up of over 2,800 novellas and counting.
  • Add the Spin-Off Atlan 1969 - 1988 with 850 issues
• Punktown - 2000 to 2014 - 12 books.
  • Also add the softcover SpinOffs, running from 1964 - 1998 with another 415 books
• Sector General - 1962 to 1999 - 12 books.
• Skolian Saga - 1994 to present - over a dozen novels plus short stories
• The Stainless Steel Rat - 1961 to 2010 - 12 books.
• Sword Art Online - 2009 to present - 26 books.
• The Third: The Girl with the Blue Eye - 1999 to present, 18 books.
• Vorkosigan Saga - 1991 to present - 15 novels plus short stories.
• Wild Cards - 1985 to present, 22 books.
• The Xeelee Sequence - 1987 to present - 9 novels and 53 short stories collected in three anthologies.

Non-Fiction

• CRC Handbook of Chemistry and Physics – 1914–present; 103 editions
• Grays Anatomy - 1858–present; 41 editions
• Robbins Pathology - 1971–present; 10 editions of Basic Pathology and 15 other books in the series

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