How would we on Earth build galactic-scale Beacons to attract the attention of extraterrestrials? An optimum tradeoff emerges by minimizing the cost of producing power density at long range. James Benford will show scaling, examples and costs. If ETI were to build a cost-optimum interstellar Beacon, how should we look for it? Jim will propose SETI search strategies, a new test for SETI Beacons and describe how observers can differentiate Beacons from pulsars or other exotic sources.