An outbreak of giardiasis occurred among people who attended a day long, job training, meeting that was held at a restaurant in Washington state. All attendees were served the same food items. Consuming ice while attending the meeting was epidemiologically associated with developing giardiasis. Among the food workers who handled ice, giardia cysts were isolated from the stool of one, and another food worker had a child at home who had giardia cysts in his stool. The restaurant had multiple sanitary violations.