Eighty-two corn dry-milling establishments in 20 states were surveyed concerning control practices for preventing the use of corn contaminated with aflatoxin or zearalenone. Prime products and by-products from each establishment were analyzed for these mycotoxins to determine whether a correlation exists between control practices and product contamination. No zearalenone was detected in any product; there was little awareness of the potential for contamination with this mycotoxin. No correlation was found between control practices and aflatoxin contamination encountered, but there was a positive correlation between aflatoxin contamination and the geographical source of the corn. Reported experimental findings in regard to the distribution of aflatoxin between prime product and by-product were generally corroborated.