The Elvish languages of Middle-earth, constructed by J. R. R. Tolkien, include Quenya and Sindarin. These were the various languages spoken by the Elves of Middle-earth as they developed as a society throughout the Ages. In his pursuit for realism and in his love of language, Tolkien was especially fascinated with the development and evolution of language through time. Tolkien created two almost fully developed languages and a dozen more in various beginning stages as he studied and reproduced the way that language adapts and morphs. A philologist by profession, he spent much time on his constructed languages. In the collection of letters he had written, posthumously published by his son, Christopher Tolkien, he stated that he began stories set within this secondary world, the realm of Middle-earth, not with the characters or narrative as one would assume, but with a created set of languages. The stories and characters serve as conduits to make those languages come to life. Inventing language was always a crucial piece to Tolkien's mythology and world building. As Tolkien stated:

The invention of languages is the foundation. The 'stories' were made rather to provide a world for the languages than the reverse. To me a name comes first and the story follows.

Tolkien created scripts for his Elvish languages, of which the best known are Sarati, Tengwar, and Cirth.