The White Spot Restaurant, in Vancouver, British Columbia, Canada, was the source of two discrete clusters of botulism cases during the latter half of summer 1985. Eight cases were recognized in the first cluster, which followed a meal at the restaurant between July 26 and August 2. An additional 26 cases were recognized in the second cluster, which followed meals eaten between August 29 and September 5. Cases were reported in Canada, the United States, and the Netherlands. There was a slow development and progression of symptoms, up to 10 days, following exposure. Cases were widely dispersed and initially involved atypical manifestations of acute botulism. Health care practitioners and specialists were misled in their primary diagnosis. As a result, many of the patients were hospitalized with a range of other neurologic and psychiatric diagnoses. A case-control study demonstrated two sandwiches on the menu to be highly associated with illness, and further analysis implicated a preparation of chopped garlic in soybean oil as the specific vehicle of intoxication. It was suspected that the product was unrefrigerated for several months before being opened. In 1989, another outbreak of botulism was linked to the same garlic in oil product.