his article documents the experiences of the Extreme Programming (XP) team at Evant with regards to the Testing aspect of XP. It highlights the benefits the team enjoys from the approach of Test-First Design and the obstacles overcome in creating testable code for the many technologies commonly in use in Web Application architectures. Testing is a fundamental aspect of Extreme Programming but is a practice that too often falls by the wayside in today's fast-paced Web Application development culture. At Evant, each of the principles of Extreme Programming has been adhered to from the beginning, and Testing is no exception. This article explains how the team at Evant has found that Testing, positioned as the drive behind development, has been critical to the success of building Evant's application at speed while maintaining a high degree of quality.