Dr. Valdes' research explores many of the issues of bilingualism relevant to teachers in training, including methods of instruction, typologies, measurement of progress, and the role of education in national policies on immigration. Specifically, she studies the sociolinguistic processes of linguistic acquisition by learners in different circumstances--those who set out to learn a second language in a formal school setting (elective bilingualism) and those who must learn two languages in order to adapt to immediate family-based or work-based communicative needs within an immigrant community (circumstantial bilingualism). Her research in these areas has made her one of the most eminent experts on Spanish-English bilingualism in the United States.

She is a founding partner of Understanding Language, an initiative that focuses attention on the role of language in subject-area learning, with a special focus on helping English Language Learners meet the new Common Core State Standards and Next Generation Science Standards (http://ell.stanford.edu).