Along with themed housing focusing on foreign languages and substance-free living, there are also "living-learning communities" which have been formed for specific social, gender-related, or academic needs.[232] An example is UNITAS, sponsored by the Department of Anthropology, where residents are assigned roommates on the basis of cultural or racial differences rather than similarities.[233] Three apartment complexes offer housing for families, graduate students, and some upperclassmen.[234] Along with the rest of campus, all residence halls, apartments, and their surrounding grounds are smoke-free.[235] As of 2008[update], 46% of all undergraduates live in university-provided housing.[236]