Axis2, the next generation of Apache Web Services middleware, is an effort to re-architecture Apache Web Service stack to incorporate the changes in Web Services. Among many improvements, Axis2 provides first class Messaging and SOAP extension supports together with a novel lightweight streaming based XML processing Model. The architecture is build on top of a simple and extensible core that provides the basic abstractions for the rest of the system. We present the design and the thought process behind the key abstractions by breaking down the architecture in to three topics, XML Processing Model, Extensible SOAP processing model and Messaging Framework. This Paper explains the overall architecture while concentrating on the three topics, and demonstrate how they all fit together to yield Axis2.