d20 Modern is a modern fantasy role-playing game system designed by Bill Slavicsek, Jeff Grubb, Rich Redman, and Charles Ryan. The system's core rulebook was published by Wizards of the Coast on November 1, 2002; by 2006, ten additional supplements were released. The game is based on the d20 System and the Dungeons and Dragons 3rd Edition ruleset. It includes various campaign settings along with the tools to build campaigns in modern/contemporary settings.