Cáin Lánamna "The Law of Couples", an Old Irish text dated to c. 700, is arguably the most important source of information concerning women and the household economy in early Ireland. The text describes all the recognized marriages and unions, both legal and illegal, and provides information regarding the allocation of property in the event of a divorce. The text was heavily glossed over a period of several centuries and provides insights into changes in the Irish legal system. This book provides, for the first time, an English translation of the entire text and all the accompanying glosses and commentary. It also includes an introduction to early Irish society, linguistic and legal notes, and a glossary to the tract.