This volume contains 27 papers selected from among those presented at the 42nd Annual Conference on African Linguistics, which took place from June 10-12, 2011 at the University of Maryland. The conference was organized around the theme "African Languages in Context," and the papers are grouped into sections on phonetics and phonology, phonology and syntax, syntax, sociolinguistics, and computational linguistics. The complete table of contents is available at http://www.lingref.com/cpp/acal/42/index.html along with abstracts and the complete papers in PDF format. This volume has been published by Cascadilla Proceedings Project, an imprint of Cascadilla Press. Proceedings from Cascadilla Proceedings Project are published in library binding, with free web access to all of the papers in the proceedings through our web site at www.lingref.com.