The purpose of this guidance document is to present guidelines and criteria for classification in order to clarify the differences between drugs and feeds, and to assist in determining the appropriate regulatory oversight for a product destined for use in livestock species. The pursued objectives are: to improve the transparency of the classification process, to increase the consistency in decisions by regulators, and make these more predictable to stakeholders; and to resolve industry confusion and to provide better guidance to manufacturers of such products regarding the appropriate regulatory department, submissions and processes for a product approval.