The game, which was released for Microsoft Windows, PlayStation 3, and Xbox 360, is set in the Mojave Desert 204 years after a devastating nuclear war.

The player can also initiate conversations with non-player characters in the form of dialogue trees, and their responses determine their reputation among the different factions.

Project director Josh Sawyer wanted the story to focus on greed and excess, and used the history of Las Vegas as an inspiration.

To design the game's map, Obsidian used data collected by the United States Geological Survey and reference photographs taken by Sawyer.

[2][5] The player is equipped with the Pip-Boy 3000, a wearable computer that serves as a menu and allows them to access items they have acquired, view detailed character statistics and active quests, and look at the map.

[12] Three major entities seek control of the Mojave Desert, which is known in-game as the Mojave Wasteland: The New California Republic (NCR) is a democratic republic that attempts to maintain law; Caesar's Legion is a violent, tribal army that is inspired by the Roman legion; and Mr. House is a mysterious businessman from New Vegas who controls an army of robots called securitrons.

Left for dead, a Securiton named Victor digs out the courier from a shallow grave, and physician Doc Mitchell nurses them back to health.

Mr. House wants to have sole control of New Vegas; if the player supports him, the overwhelming Securitron army forces both factions to leave the area.

Alternatively, if the player wishes the Mojave Wasteland to remain independent of leadership, they can take control of Mr. House's Securitron network with the help of Yes Man.

[15][16] The game was cancelled in December 2003 following the financial issues faced by Black Isle Studios' publisher, Interplay Entertainment.

[22] Bethesda's creative director, Todd Howard, lobbied for a full game instead of an expansion pack and, based on their experience with the Fallout series, suggested Obsidian.

[15][18] Other proposals included setting the game in a city based on Reno, Nevada, and allowing the player to play as a human, a ghoul, or a super mutant.

[15] At the behest of project director Josh Sawyer, Obsidian repurposed digital assets from the canceled Alien game for Fallout: New Vegas.

[18] Sawyer felt the factions would realistically be most concerned about access to water in the desert setting and Hoover Dam became a focal point for worldbuilding.

[24] Other differences include a warmer color palette for the graphics, and the inclusion of local flora, such as Joshua trees and prickly pear cacti.

No Obsidian staff had worked with Gamebryo, so the company hired a modder with experience making mods for The Elder Scrolls IV: Oblivion.

"[29] Zur was inspired by the soundtrack for the film There Will Be Blood; he worked with audio director Scott Lawlor to compose music for a string quartet.

[29] In addition to the original soundtrack, Fallout: New Vegas includes licensed music to which the player can listen via in-game radio stations.

[30] The game also includes celebrity voice acting from Rene Auberjonois, Felicia Day, John Doman, Michael Dorn, Kris Kristofferson, Zachary Levi, Wayne Newton, Ron Perlman, Matthew Perry, and Danny Trejo.

[39] Fallout: New Vegas suffered from numerous glitches upon release, including crashes, corrupted saved games, and frame rate issues.

[44] The final story-driven DLC was Lonesome Road, in which the player tracks another courier named Ulysses, who rejected the job of delivering the Platinum Chip to Mr.

[15] Bethesda offered Obsidian a bonus payment if any version of the game received a rating of 85/100 or higher on the review aggregator website Metacritic.

[51][55][57] Craig Pearson of PC Gamer described the story as a significant improvement over that of Fallout 3, and appreciated the way factions adapt to the player's choices and previous actions.

[57] The British version of Official Xbox Magazine called the story "staggering in scope and consistent in quality", and particularly praised the final quest.

[52][53] Game Informer's Andrew Reiner wrote: "Obsidian's writing is top notch (especially the dialogue), and I wanted to see more from most of the characters I met, but none of the scripted moments deliver the nuclear bang that Bethesda achieved".

[56] The newly added gameplay mechanics, such as faction reputation and Hardcore Mode, were well received; reviewers said they add an additional layer of complexity over Fallout 3.

If you were able to look past the issues that plagued Fallout 3 and [The Elder Scrolls IV: Oblivion] before it, New Vegas will eventually show you a real good time.

[B] In a retrospective article about the Fallout series, Ian Dransfield of Retro Gamer stated: "New Vegas served as the balance between Bethesda's new 3D approach, and Black Isle/Interplays focus on traditional [role-playing] mechanics".

[16] Eurogamer's Emma Kent wrote: "it felt like even the smallest story was carefully crafted to maintain interest and deliver a rewarding kicker ... on the macro scale, New Vegas took a more serious tone by weaving a complex power struggle that mirrors many current real-world conflicts".

[77] Fallout: The Frontier, a mod that added a new map to the game, was the subject of media attention due to its large size and controversial content.