| ARDA | Variant | Designer | Players |
| ph02 | Iberian Diplomacy | Macario Reyes | 5 |
| gf26 | Ice Age Diplomacy | Jim Penman | 8 |
| rb91 | Illegal Gunboat | Patrick Lafontaine | 7 |
| rg16 | Illuminated Vain Rats | Author Unknown | 8 |
| ru05 | Impassable Diplomacy | Lee Kendter, Jr. | 7 |
| ar01 | Imperator | Richard Vedder | 5 |
| rm50 | Imperial Diplomacy | Pete Calcraft and Andy Poole | 7 |
| gh13 | Imperial Diplomacy II | Michael David Roberts | 13 |
| ag05 | Imperialism IX (Peloponnesian War I) | Rod Walker | 9 |
| ag01 | Imperialism IX-R (Peloponnesian War II) | Rod Walker | 9 |
| qh06 | Imperialism VII | Rod Walker | 6 |
| gp16 | Imperialism VIII | Rod Walker | 9 |
| gp06 | Imperialism VIII-RR | Rod Walker | 9 |
| qh01 | Imperialism VII-R (Things to Come II) | Rod Walker | 6 |
| ac06 | Imperialism XI | Rod Walker | 7 |
| gp01 | Imperialism XV | Rod Walker | 11 |
| vh04 | Imperialism XVI | Glenn Overby | 7 |
| ei01 | India 1501 | Stephen Agar | 5 |
| ei04 | India II | Stephen Agar | 5 |
| np01 | Indianomacy II | Wayne Hoheisel | 8 |
| np03 | Indians of the Great Lakes | Christopher Carde | 9 |
| es01 | Indonesian Diplomacy I | Russell Fox | 8 |
| es06 | Indonesian Diplomacy II | Russell Fox and Fred Davis | 7 |
| rd15 | Infiltration | Elmer Hinton | 7 |
| qh17 | Influential Diplomacy | Mark Boyle | 5 |
| vb04 | Inside Out Diplomacy | Bruce Linsey (map reversal) | 7 |
| rm65 | Insurrection | Glenn Overby | |
| re19 | Interest of Trade … | Thomas M. Kane | 7 |
| rv20 | International Relations | Michael Golbe | 7 |
| sg02 | Interplanetary Warfare | Glenn Reed | 5 |
| sg07 | Interstellar Conquest | Larry Rainbow | 6 |
| sg11 | Interstellar Diplomacy I | Lew Pulsipher | |
| sg12 | Interstellar Diplomacy II | Lew Pulsipher | |
| sg03 | Interstellar Diplomacy III | Lew Pulsipher | 5 |
| sg13 | Interstellar Diplomacy IV | R. Prevot | 5 |
| rx02 | Intimate Diplomacy I | Steve Wyatt | 2 |
| rx03 | Intimate Diplomacy I-A | Adrien Baird, Steve Doubleday and Steve Wyatt | 2 |
| rx29 | Intimate Diplomacy II | Dave Allen | 2 |
| rr21 | Intimate Seismic Diplomacy | Matt Quartemain | 2 |
| rx12 | Intimate Stab | Matt Quartemain | 2 |
| rx14 | Intimate Stab II | Michael Heaton | 2 |
| ru06 | Into the Void | Andy Bate | 7 |
| rm06 | Intrigue | Steve Doubleday | |
| rb110 | Invasion | Michael Ribciro | |
| ab01 | Invasion 44 AD | John Robertson | 7 |
| ar12 | Invasions I | Cristiano Corte Restitutti | 16 |
| ar13 | Invasions II | Cristiano Corte Restitutti | 16 |
| ar15 | Invasions III | Cristiano Corte Restitutti | 11 |
| re16 | Investment Diplomacy | Larry Cronin | 7 |
| rr05 | Irish Diplomacy I | Colin Walsh | 21 |
| rr20 | Irish Diplomacy II | Mark Nelson | 7 |
| em15 | Islam | Max Feron (Rules in French) | 7 |
| ru08 | Isostatic Diplomacy | Steve Doubleday | 7 |
| rm80 | It Came From Outer Space | Dan Percival | |
| pw01 | Italy, 1500 | C. Alexander | 9 |
| rb73 | Jellyfish Diplomacy | Jesse Severe | 7 |
| em04 | Jihad I | Richard Vedder | 7 |
| em02 | Jihad II | Richard Vedder | 7 |
| ej01 | Jimmu | Mike Mills | 6 |
| ej02 | Kamakura | commercial game by West End Games, Inc. | |
| es07 | Kampuchea | Lachlan Olive | 7 |
| es08 | Kampuchea II | Lachlan Olive | 5 |
| lc04 | Karibik | Martin Asal | 8 |
| rs29 | Karma League | Jeremy Maiden | 7 |
| rb17 | Key’s Rule Diplomacy | Jeff Key | 7 |
| rt08 | Killtest, 3 x 3 Team game (Austria omitted) | Andy Mansfield | 6 |
| fa01 | Kregen | Ken St. Andre | 8 |
| cm01 | Kriegsmarine Variation | A. Phillips (CE 1) | 7 |
| rd01 | Kriegspiel Diplomacy I | Buddy Tretick | 7 |
| rd03 | Kriegspiel Diplomacy II | Buddy Tretick (includes rd04) | 7 |
| rd04 | Kriegspiel Diplomacy III | Buddy Tretick (included with rd03) | 7 |
| rd07 | Kriegsplomacy (Kriegspiel Diplomacy IV) | Allen Wells and Don Woods | 7 |
| xo01 | L’Imperialisme I (ex “xm11”) | Lew Pulsipher | 8 |
| xo02 | L’Imperialisme II (ex “xm14”) | Lew Pulsipher and Fred Davis (includes xo03 and xo04) | 7 |
| xo03 | L’Imperialisme II-A (ex “xm15”) | Lew Pulsipher and Fred Davis (included with xo02) | 8 |
| xo04 | L’Imperialisme II-B (ex “xm16”) | Lew Pulsipher and Fred Davis (included with xo02) | 7 |
| hn04 | La Revolution | John Robertson | 6 |
| cb47 | Land Bridge Diplomacy (I-A) | Lee Kendter, Jr. | 7 |
| cb49 | Land Bridge II Diplomacy | Lee Kendter, Jr. | 7 |
| cb58 | Land Bridge III | Lee Kendter, Jr. | 7 |
| lb02 | Latin American Diplomacy | Michael Zmolek | 12 |
| ar14 | Latin Wars | Stephen Agar | 6 |
| rs53 | Layered Diplomacy | Ralan Hill | 7 |
| rn24 | Leadership Rules Module | Lew Pulsipher and Fred Davis (ex “ra07”) (CE 11) | |
| em10 | Lebanon | Lachlan Olive | 6 |
| em11 | Lebanon II | Lachlan Olive | 5 |
| qh14 | Lebensraum | R. Egan | 5 |
| qh18 | Lebensraum II | Allan McGregor | 7 |
| qh15 | Lebensraum III | Allan McGregor | 7 |
| rb11 | Lebling Variant | D. Lebling | 7 |
| rb51 | Legalese Diplomacy | Peter McDonald and Andrew England | 7 |
| ac04 | Legion | John Biehl | 5 |
| ao02 | Legion II | Florent Montauban | 7 |
| fn04 | Lemurian Diplomacy | S. Gunnell | 4 |
| ma01 | Lest Darkness Fall Diplomacy | Greg Costikyan | 7 |
| ra10 | Life Diplomacy | Jef Bryant | 7 |
| xm17 | LiMa 3 (a Youngstown Supplement) | J. Macedoni and M. Liesnard | 10 |
| xm24 | LiMa 5 – Definitive | M Liesnard, J-P Macedona, G.A. Bryant and P. Lafontaine | 10 |
| xm18 | LiMa 5 (a Youngstown Supplement) | J. Macedoni and M. Liesnard | 10 |
| cb12 | LiMa I | Jean-Paul Macedoni, Colin Hemming and Michel Liesnard | 7 |
| cb24 | LiMa Ib | Liesnard, Macedoni, and Hemming (includes cb25) | 7 |
| cb25 | LiMa IIb | Liesnard, Macedoni, and Hemming (included with cb24) | 7 |
| rd20 | Limited Intelligence | Ian Whitchurch | 7 |
| gp36 | Lincoln’s Nightmare | John Armstrong | 17 |
| rd32 | LIPDIP | Michael Norrish | 7 |
| rm68 | Literomacy | Michael Gibson | 7 |
| un01 | Lizard | K. St. Andre | |
| cn13 | Loeb’s Nine Player Variant | Danny Loeb | 9 |
| ug02 | Logical Diplomacy I | Allan Ovens | 6 |
| ug03 | Logical Diplomacy II | Lew Pulsipher | 5 |
| pe17 | London Nights | Andy Mansfield | 7 |
| ap02 | Lord of Hosts | Tim Collieu | 6 |
| ts02 | Lord of the Rings Diplomacy I | Jeff Key | 6 |
| ts12 | Lord of the Rings Diplomacy II | Jeff Key | 6 |
| pw07 | Low IQ Machiavelli | Rowland Goodman (requires pw02) | 8 |
| rr23 | LSD Diplomacy | Gavin Addison | 7 |
| ug04 | Lunatic Diplomacy I | Thomas Galloway | |
| ug07 | Lunatic Diplomacy II | Thomas Galloway | |
| ug10 | Lunatic Diplomacy III | Thomas Galloway | 6 |