Five confirmed, and one suspect, case of campylobacteriosis were found to be associated with drinking milk from a dairy in Park County, Wyoming. All persons had consumed raw milk from the dairy sometime in late June or early July. Other possible links between the ill persons were investigated, but no other associations were found. Milk samples from the dairy and from one ill person’s refrigerated milk were analyzed, but none revealed the presence of Campylobacter. Since Wyoming state regulations prohibited the sale or distribution of raw milk, a cease and desist order was issued to the dairy.