Mapudungun, the language of the Mapuche of modern south-central Chile and southwestern Argentina, did not have a writing system when the Spanish arrived. There have been a number of proposals for orthographies or Mapudungun alphabets, all of them using Latin script, but no consensus has yet been achieved between authorities, linguists and Mapuche communities on the one to be used.
The main systems are the following:
- Alfabeto Mapuche Unificado ("Unified Alphabet"), used by Chilean and Mapuche linguists and used in most of the scientific literature about the language.
- Grafemario Raguileo, made by Anselmo Ranguileo Lincopil (1922–1992) and defended by the indigenous Mapuche organization Consejo de Todas las Tierras.
- Azumchefi (also called Azümchefe), proposed by the Corporación Nacional de Desarrollo Indígena (CONADI) as a summary of about six earlier proposals, and recognized by the Chilean Ministry of Education, but not widely used.
- The Nhewenh writing system, an online proposal  by Heinrich Puschmann, based on the ASCII character set facilitate the usage of the language on the Internet.
A more thorough look at the sounds of Mapudungun is available here.
Mapudungun has the following consonant system.
(*) Raguileo does not distinguish between /s/ and /ʃ/ or between /t̪/ and /t/. Also, Raguileo aims to use only one grapheme for each phoneme (no digraphs) so he uses some letters from the alphabet in an unexpected way.
Mapudungun has six vowels. The three high vowels also have corresponding approximant consonants.