A new wireless telemetry system has been field tested in a variety of conditions in Saudi Arabia with excellent reliability. This wireless system enables bi-directional communication between the surface and downhole tools during downhole testing (Drillstem Test (DST) / tubing conveyed perforation (TCP)) operations by using an electro-magnetic signal. The wireless telemetry is used to transmit bottomhole pressure and temperature to the surface and permits control of downhole tools. This paper will describe the operating principle of the wireless system, present examples of how real-time bottom-hole data have been used to optimize the testing operations and summarize the key benefits achieved with this new technology. The real time analysis of well testing data during well flow and shut-in was effective in adjusting the test duration. The wireless telemetry eliminated the need for well intervention, which simplified the operation and eliminated the possibility of loss of data.