The present document gives an introduction and overview of the complete Digital Enhanced Cordless Telecommunications (DECT) Common Interface (CI). The present document contains an abstract of the other parts of the DECT standard together with a general description of: ? the objectives of the present document; ? the DECT Common Interface; ? the protocol architecture of DECT. The present document also provides an extensive vocabulary; in particular it contains the common definitions of all the technical terms used in different parts of the present document. The present document includes New Generation DECT@ a further development of the DECT standard introducing wideband speech@ improved data services@ new slot types and other technical enhancements.