Design features of Godiva II, the improved pulsed-reactor successor to Lady Godiva, are discussed together with characteristics of power excursions, and performance is compared with that of the original Godiva. Measurements of the wait time between stepwise reactivity insertion and the occurrence of a burst are presented and compared with theory based on a statistical model of fission chains. Analytical and numerical solutions of the reactor equations are developed to reproduce experimental data and extrapolate to higher energy release. Consideration is also given to perturbations arising from room-returned neutrons. Two different modes of operation are discussed and some design problems of Godiva-type pulsed reactors are briefly mentioned. Typical bursts are illustrated with peak powers up to 13,000 Mw and widths at half-maximum down to 35 µsec.