Microsoft has announced the initial list of Xbox games which will be compatible with the Xbox 360 when the new console launches later this month, with over 200 of the existing console's titles to be supported from the outset.
212 titles in total are included on the initial compatibility list, including Halo and Halo 2, Rockstar's Grand Theft Auto series and Tecmo's Ninja Gaiden and Dead or Alive 3 titles, with more games set to be added to the list over time.
However, not all titles will work straight out of the box - users will need to connect the Xbox 360 to the Xbox Live service, download emulation software and reboot the console before Xbox titles can be played.
Those without the Xbox Live service can download the software from Xbox.com and burn it onto a CD for loading onto the Xbox 360, or can request that it is delivered to their house for a shipping and handling fee.
According to Microsoft corporate VP Todd Holmdahl, the firm's goal "remains to make as many games backward compatible as possible" - with the current figure of 212 titles representing under a quarter of all titles released for the Xbox to date in North America.
The list of games, which Holmdahl says will be updated regularly with new supported titles after the launch of the Xbox 360, is a definitive list of what will and won't run on the new system - games not on the list will present an error message if users try to run them.
Backward compatibility will also not be available to users who opt for the Xbox 360 Core System pack, as the Core System ships without a hard drive, which is required to play Xbox games on the next-gen console.
Another snag with the backwards compatibility system being employed between Xbox and Xbox 360 is that there's no way to transfer save data or downloaded content from one console to the other - and users will have to pay for premium content they already own on their Xbox a second time if they want to use it on Xbox 360.
However, Microsoft has succeeded in overcoming a number of other potential problems - including Xbox Live play, which will be completely cross-compatible between Xbox and Xbox 360 consoles.
Xbox games will also be upgraded by the emulation software to play in the new HDTV modes supported by the next-gen console.
A full list of the games which will be supported by the Xbox 360 at its US launch has been published on the Xbox.com website.