Romansh language the most comprehensive collection of Romansh words, which can also be used in the idioms with the necessary phonetic shifts. The signatories of "Pro Rumantsch" stress that Romansh needs both the idioms and Rumantsch Grischun if it is to improve its chances in today's communication society. In Switzerland, official language use is governed by the "territorial principle": Cantonal law determines which of the four national languages enjoys official status in which part of the territory. Only the federal administration is officially quadrilingual. Romansh is an official language at the federal level, one of the three official languages of the Canton
Jauer dialect (Romansh) 2007, a collection of short stories written in Jauer ("Dschon Uein id atras istorias grischunas") was published In official use and as the language of school, Vallader has traditionally been used in the Val Müstair. In 2007, the valley was one of the first municipalities of the canton to introduce the pan-regional Romansh variety Rumantsch Grischun as the language of schooling and official use. In 2012 however, a municipal assembly voted to return to the use of Vallader in schools. As with other Romansh speakers, virtually all speakers of Jauer with the exception of children below school-age are also proficient