Growth promotion testing of culture media appears to be a trivial test, but this perception is deceiving. Almost everyone can agree that with the criticality of microbiological tests, it is extremely important that culture media performs properly. Culture media is used in most assays in a microbiology laboratory, and if the media does not properly support growth, false negative results may be obtained. Likewise, contaminated media may yield false positive results. Opinions on when and how the testing should be performed sometimes vary within the pharmaceutical industry.