This Appendix is intended to provide relevant information for federal and state officials and other interested parties who will participate in making decisions related to use of vaccine as an aid to control an outbreak of foot and mouth disease (FMD) in the U.S. The following topics are presented and discussed:  Important characteristics of FMD: Characteristics of vaccines; Strategies for vaccine use; Various factors that must be considered when designing an effective vaccination program. The USDA-APHIS has a separate document, FMD Response Plan: The Red Book, which identifies the capabilities needed to respond to an FMD outbreak in the United States as well as identifying all the critical activities involved in responding with the corresponding time-frames. Please refer to that document for those specific details.