A series of deuterium permeation experiments were carried out using a nickel membrane in an elevated temperature range of 450-850 degrees C for application to nuclear fusion and nuclear hydrogen technologies. A complete set of permeability, diffusivity, and solubility data for deuterium in nickel was successfully determined. The results of this study were compared with results previously reported by other authors. The results for deuterium were also compared with the results for hydrogen to estimate the isotope effect. The results for and a discussion of deuterium permeation and the isotope effects in nickel are presented. Copyright (C) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.