The state of Turkey placed an official prohibition on the use of the letters Q, W, and X from 1928 to 2013. The policy was a consequence of the country's 1928 alphabet reform, which replaced the Ottoman Arabic script with a modified Latin alphabet consisting of 29 letters. Because these three letters were excluded from the official Turkish alphabet, their use in official documents, personal names, and public communications was restricted for decades. While the policy was presented as a linguistic standardization measure, it became closely associated with the suppression of Kurdish linguistic and cultural expression because the Kurdish Latin alphabet uses all three letters extensively. The restrictions remained in force until reforms introduced in 2013 legalized their use, although the letters were not incorporated into the official Turkish alphabet.
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