An error appeared in my article, "Science policy for the 1970's: Canada debates the options" (12 Jan., p. 151). The article credits two Canadian researchers, Frederick Banting and Charles Best, with the "synthesis of insulin." Actually, their pioneering achievement was the preparation of an active extract of this substance from animal tissue for the first time. The synthesis of insulin was achieved more recently by American and Chinese researchers. I am indebted to R. A. Cleghorn of McGill University for calling my attention to this regrettable slip.