The ratio of neutron capture to fission cross sections, α, has been measured for U233, U235, and Pu239 at 9 incident neutron energies from 30 kev to 1000 kev. A pulsed and collimated neutron beam is passed through a target placed at the center of a large, cadmium-loaded, liquid scintillator. Capture and fission events are detected by means of their prompt gamma rays; elastic and inelastic scattering events are discarded because of their smaller pulse height. Fission is identified by the delayed pulses produced by capture in the scintillator of the fission neutrons. Corrections are applied for the fission events not followed by delayed neutron pulses and for the effect of background counts. This procedure yields values of 1 + α to an accuracy of 1 or 2%.