M. Paul Lewis served as general editor of Ethnologue: Languages of the World from 2004 to 2016, and is a Senior Consultant in Sociolinguistics with SIL International. His primary research and publication interests are in language maintenance, shift and death, language policy and planning, and language documentation. He has authored, co-authored, or edited more than 50 publications. Along with Gary F. Simons, he is a developer of the Expanded Graded Intergenerational Disruption Scale (EGIDS) and the Sustainable Use Model (SUM). Beyond his duties as general editor of the Ethnologue (www.ethnologue.com), he has primarily done research, consulting and training in sociolinguistics with SIL International in Africa, Australia, Asia, Central America, Europe and North America.