The Vietnamese languages are part of a sign language area that includes indigenous sign languages of Laos and Thailand, though it is not known if they are genealogically related to each other. The influence of LSF may have obscured the links: the highest cognacy is with Haiphong Sign, which has been the least influenced by LSF.
There are attempts to develop a national standard language, Vietnamese Sign Language (Vietnamese: Ngôn ngữ ký hiệu Việt Nam).
Woodward, James (2000). Sign languages and sign language families in Thailand and Viet Nam, in Emmorey, Karen, and Harlan Lane, eds., The signs of language revisited : an anthology to honor Ursula Bellugi and Edward Klima. Mahwah, N.J.: Lawrence Erlbaum, p. 23-47
Woodward, James; Thi Hoa, Nguyen; Tran Thuy Tien, Nguyen (2004). Providing higher educational opportunities in Deaf adults in Viet Nam through Vietnamese sign languages: 2000-2003. In: Deaf Worlds 20: 3 (2004) - pp. 232–263
^a Sign-language names reflect the region of origin. Natural sign languages are not related to the spoken language used in the same region. For example, French Sign Language originated in France, but is not related to French. Conversely, ASL and BSL both originated in English-speaking countries but are not related to each other; ASL however is related to French Sign Language.
^b Denotes the number (if known) of languages within the family. No further information is given on these languages.