Stool specimens from 124 international travelers with acute diarrhea were tested for the presence of enteropathogens. Noroviruses (NoVs) were the second most commonly identified enteric pathogen in diarrheal stool samples (21/124, 17%), exceeded only by enterotoxigenic Escherichia coli (50/106, 47%). This study indicates that NoV is an underappreciated cause of traveler's diarrhea.