The Ph.D. program provides both a broad grounding in linguistics and the opportunity for specialization within the broad areas of formal linguistic theory, second language acquisition, language variation and sociolinguistics, and historical (Indo-European) linguistics. The programs of study constructed by individual students and their advisory committees focus on two specific fields of concentration within these broader areas. The programs of study also may include courses or research projects in related disciplines such as computer science, philosophy, or in the history or structure of a specific language or languages. Students must fulfill all requirements of the Graduate School for the Ph.D. degree, including the residence requirement and time limits see the Graduate Bulletin for details