This part of ISO 28560 specifies a data model and encoding rules for the use of radio frequency identification (RFID) tags for items appropriate for the needs of all types of libraries (including academic, public, corporate, special and school libraries). The rules for encoding a subset of data elements taken from the total set of data elements defined in ISO 28560-1 are based on ISO/IEC 15962, which uses an object identifier structure to identify data elements. This part of ISO 28560 defines the technical characteristics required to encode the data elements defined in ISO 28560-1 in accordance with ISO/IEC 15962. These subsets of data elements can be different on different items in the same library. The encoding rules also enable the optional data to be organized on the RFID tag in any sequence. In addition, the encoding rules provide for flexible encoding of variable length and variable format data. This part of ISO 28560 provides essential standards-based information about RFID in libraries. A source of additional information about implementation issues is provided in Annex A.