Abstract: Interoperability is achieved between wireless user communication devices that have different speech processing formats and/or attributes. A first wireless user communication device includes a primary speech codec that encodes a first speech message using a first speech encoding format. The encoded speech is then sent to a second wireless user communications device that includes a primary speech codec supporting a second speech encoding format. The first user device receives from the second user device a second speech message encoded using the second speech encoding format. The second speech message is then decoded by the first user device using a second speech decoder supporting decoding of the second speech encoding format. But the first communication device does not support speech encoding using the second speech encoding format—regardless of whether the first communication device includes or does not includes an encoder for encoding speech using the first speech encoding format.