The Tetris Guideline is the current specification that The Tetris Company enforces for making all new (2001 and later) Tetris game products alike in form. A mode labeled "standard" or just plain "Tetris" will adhere to the Guideline more closely than other modes.

All of this info is confidential, properietary trade secrets.

The extent to which the Guideline specifies the speed curve, the scoring system, and other aspects not listed on this page, is not yet known to the public.

Although Guideline-compliant games share many traits, they also have differences in many aspects as well. There are a few instances where a game will break a trait which is shared by all other games thought to be compliant. Examples of this include the lack of the hold function and the T-spin's ability to start and continue Back-to-Back chains in iPod Tetris, and the inverted rotation button layout of TGM3 and TGM ACE (or Kiwamemichi, depending on interpretation). No explanations have been given for the reasons of these games' deviations.

Certain games, such as Tetris Online (Japan) and the handheld electronic games by Radica Games defy the guidelines despite having "Authentic Tetris Game" labels. In other words, tetris games don't have to follow the Guideline to be official.

Guideline Versions

Henk Rogers has been quoted as revising the guideline annually. This may only adhere to 2005 and later, as so far only guideline 2002, 2005 and 2006 have been known to be in existence, and guideline 2002 games have been built from scratch and released as late as 2005.

So far, the first confirmed guideline 2005 games (TGM ACE) has been released in December 2005, while the first confirmed guideline 2006 game (Tetris: New Century, although iPod Tetris released earlier behaves similarly) was released in September 2006. Therefore, it can be conjectured that the schedule of a new guideline version is released somewhere between the middle to the latter half of the year.

While many games have no publicly visible indication of the guideline version by the developer or publisher, some games have had their exact guideline versions made clear by them. They are listed in the Guideline compliant game differences page.

See also

• Guideline compliant game differences
• Tetris Worlds, Tetris Deluxe, and Tetris Zone, considered by many to be the "reference" implementations of the Guideline at the respective times of the games' releases.
• Tetris DS, another popular game that is compliant with the Guideline

References

• Edge magazine's interview with Henk Rogers (web archive) Henk first reveals the existence of the Guideline.
• Tetris from the Top: An interview with Henk Rogers that reveals some aspects of the Guideline
• EA Tetris product page, with official names for some Guideline features