The Cantonese Transliteration Scheme (), sometimes called Rao's romanization, is the romanisation for Cantonese published at part of the Guangdong Romanization by the Guangdong Education department in 1960, and further revised by Rao Bingcai in 1980. It is referred to as the Canton Romanization on the LSHK character database.
The system is not used in Hong Kong where romanization schemes such as Hong Kong Government, Yale, ILE, and Jyutping are popular, though it can be seen in works released in the People's Republic of China regarding Cantonese. Some of the non-professional Guangzhou-language tutorials and dictionaries currently published in mainland China also use this scheme.
Unlike the other Cantonese romanization schemes, Guangdong romanization indicates a difference between the alveolar consonants z, c, s and the alveolo-palatal consonants j, q, x. Cantonese typically does not differentiate these two types of consonants because they are allophones that occur in complementary distributions. However, speech patterns of most Cantonese speakers do utilize both types of consonants and the romanization scheme attempts to reflect this.
Some publications may not bother with this distinction and will choose just one set or the other to represent these consonants.
Finals consist of an optional medial and an obligatory rime.
The only recognized medial glide in the Cantonese Guangdong romanization is u, which occurs in syllables with initials g or k and rimes that begin with a, e, i, or o. In other romanization schemes, this medial is usually grouped along with the initial as gw and kw, but Guangdong romanization attempts to preserve it as a medial. For simplicity, the u is sometimes grouped with the initials anyway as gu and ku.
The u medial can occur without an initial, but in that case it is considered the same as the initial w. The same is true for the medial i, which is only recognized as the initial y.
There are nine tones in six distinct tone contours in Cantonese. In Guangdong Romanization, one may represent the entering ( rù) tones either together with tones 1, 3, and 6, as in the other Cantonese romanization schemes, or separately as tones 7, 8, and 9. Syllables with entering tones correspond to those ending in -b, -d, or -g.
Sample transcription of one of the 300 Tang Poems by Meng Haoran: