Actual software metrics from a team that used Extreme Programming for embedded software development will be presented, along with an account of mistakes made and recovery. There will be ample time to relate this experience to the challenges faced. The purpose is to provide unbiased, thorough information about XP so you can determine whether to use it, and how to get started. The experience presented is from a software-intensive 32 bit embedded project that used multitasking. This scientific instrumentation application involved soft real-time deadlines, and produced approximately 30,000 lines of code.