Star Trek: Year Four was a six-part comic miniseries written by David Tischman and published by IDW Publishing. It was be IDW's third Star Trek miniseries, the second TOS miniseries and second project by David Tischman following his work on IDW's premier series The Space Between. It was published in an omnibus book in March 2008.
Space. The final frontier. This is the voyage of the Starship Enterprise. Her five-year mission to explore strange new worlds? It continues here, with the launch of "Year Four" in the Original Series' five-year mission.
The series is set in what would have been Star Trek: The Original Series' fourth season, continuing the five year mission of the USS Enterprise under Captain James T. Kirk. The series acknowledges Star Trek: The Animated Series, also set in the fourth year of the Enterprise's mission, with appearances by Arex and M'Ress.
The series was illustrated by several artists; Steve Conley, Gordon Purcell, and Rob Sharp & Joe Sharp, all colored by Leonard O'Grady. All issues stuck to a strict panel layout, with four wide panels per page, intended to emulate a widescreen television screen to try and make the issues feel more like episodes of the series (though of course being filmed in the 1960s The Original Series episodes are not widescreen). The layout was only occasionally broken to include larger full page illustration of key dramatic moments.
Drawing inspiration from many TOS episodes, several issues were commentaries on present-day issues, including cloning, reality television, oil and the Iraq War, or a look at present day science, with a 23rd century take on particle accelerators.
A continuation of the series began in May 2008 in Year Four: The Enterprise Experiment, by D.C. Fontana and Derek Chester. Beyond that IDW have vague plans for two more Year Four miniseries, making a total of twenty-two issues, equivalent to a full season of The Original Series, after which they plan to continue on to Year Five miniseries’. 
|Title/Number||Issue 1||Issue 2||Issue 3||Issue 4||Issue 5||Issue 6|
|Artist(s)||Steve Conley||Gordon Purcell||Rob & Joe Sharp||Steve Conley||Gordon Purcell|
|Published||25 July 2007||5 September 2007||3 October 2007||17 October 2007||19 December 2007||23 January 2008|
|Steve Conley covers|
|Joe Corroney covers|
|Retail incentive covers|
Each issue of this series was available in three covers. Two covers were distributed in equally wide availability, one each by Steve Conley (with colors by Leonard O'Grady) and Joe Corroney. The third cover for each issue was a more limited availability retail incentive cover, which was either a sketch version of the Corroney cover or a photo-cover.
In addition to the six full issues, the series was preceded by "Captain's Personal Log", a short comic published in Focus on... Star Trek. The story was written by David Tischman with art by Leonard O'Grady and acted as both an epilogue to the final TOS episode: "Turnabout Intruder" and a teaser for the ongoing voyages of the Enterprise depicted in this series.