World War I has passed from living memory into the history books, receding far enough into the distance to provide a genealogical challenge. In order to reconstruct the lives and locate the records of those who served, fought, volunteered, or were conscripted, we must rely on a vast but relatively unknown body of resources. Counting all combatants, the number of men who served in the Great War runs into the millions; needless to say, finding records on them in the two dozen countries that participated in the war is a daunting and laborious task--now made infinitely simpler with the publication of this magnificent guide to WWI service records. The only book of its kind, this ambitious effort to catalogue service records and related sources is international in scope, covering the soldiers of all countries participating in the war, from Britain, Germany, and France, to Russia, Canada, and the U.S.; and from India, Australia, and Japan, to South Africa and Brazil! This is a key to a motherlode of genealogical data and should grow in value as our need for WWI-era information increases. Right now it represents a whole new path in genealogical research, with fresh possibilities and discoveries at every turn.