The Interlaboratory LMFBR Reaction Rates program involves the determination of rates of neutron-induced reactions by the measurement of gamma-ray spectra from the decay of radioactive reaction products. A goal of the program is to determine certain nonfission reaction rates to an accuracy of ±5% and certain fission-product rates to ± %. These determinations require a knowledge of two nuclear decay scheme parameters: (a) the half-life, and (b) one or more absolute gamma-ray intensities. An evaluation of the experimental data on these parameters has been carried out for 20 isotopes, including 6 fission products. The uncertainties in these parameters have also been evaluated.