Detectingand respondingto security and privacythreats to ElectronicProductCode(EPC)andRadioFrequencyIDen- tification (RFID) technologies are becoming major con- cerns of information security researchers. However, and before going further in these activities,an evaluationof the threats in terms of importance must be done. We present such an evaluation. Our analysis of the threats is based on a methodology proposed by the European Telecommunica- tions Standards Institute (ETSI). According to this method- ology, we rank the threats to EPCnetworksin order of rele- vance. Thisassesmentisintendedtoprioritizethreatsforfu- ture research on appropriate countermeasure mechanisms.