Book excerpt: The purpose of this volume is to gather the latest experimental results from the H1, ZEUS and HERMES collaborations and to capture new trends in HERA phenomenology. The presentations are by experts for experts, but are suitable for a mixed readership of both theoreticians and experimentalists. H1 members also cover ZEUS results and vice versa. This is the place where discrepancies between experimental data and theoretical predictions are pointed out and ventilated and where projects to be launched in the future are identified.