John Rothgerber has an M.A. in TESOL and Applied Linguistics and a Ph.D. in Second Language Studies from Indiana University. He has taught English as a foreign/second language for over 20 years in both Japan and the United States. His research focuses on second language phonology. Specifically, he studies how speech sounds are perceived, stored in the mind, and produced by language learners. In addition, he studies how pronunciation instruction can be implemented and improved in the classroom.