ABSTRACT
This chapter presents the research questions which guided the study and also presents the information regarding the consultants and the procedures for data collection, and methodology. Mario speaks both Spanish and Nahuatl on a daily basis, and he has been training to become a bilingual teacher in a school located in the mountains surrounding the Tehuacan Valley. Because of Mario's late exposure to Spanish, data collected in sessions with him were regularly cross-checked with Alberto and Jorge. Alberto explained that in the company of close friends and peers it is the typical way of talking, but it is looked down upon by monolingual Spanish speakers in the big city and sometimes by older Nahuatl speakers in San Sebastian. The general and widespread practice of code switching, presenting the case of Spanish-English code switching in Los Angeles and the US, gives a useful illustration that Spanish is the language of prestige in this bilingual community, unlike the situation in United States.
