Microbiological surveys of post-processing can handling equipment were conducted in three low-acid food canneries to identify the source and numbers of mesophilic anaerobic sporeformers isolated from post-processing spoilage of cans packed at those canneries. Significant numbers of spores of these organisms were found on various equipment and can tracks. The spores were also isolated from the can cooling waters in two of the canneries and in numbers higher than have been reported previously. No correlation was noted between mesophilic anaerobic spore counts and total aerobic counts in samples obtained from the surveys. Clostridium botulinum was not isolated from any of the survey samples. A medium useful in the isolation of mesophilic anaerobic sporeformers is described.