The IEEE 802.16 working group is the body tasked to determine the final specifications to be included in the WiMAX specification.  What this body does not do is ensure commercial compatibility with the standards.  The IEEE 802.16 standard is similar, but not exactly the same as the European driven HiperMAN or the Korean WiBro/Mobile WiMAX standard.  However, the IEEE 802.16 standard incorporates support for both HiperMAN and WiBro/Mobile WiMAX.  The current active 802.16 standards include both 802.16d (or 802.16-2004 - Fixed WiMAX) and 802.16e (or 802.16-2005 Mobile WiMAX).  However, the IEEE is also working on an extension of the 802.16e version called 802.16m, which will offer improved throughput and capability.