It has been well established that hydrogen will react directly and reversibly with a large number of metals and alloys to form metallic hydrides. Extensive research has been done over the years to improve properties of these hydrogen storage media and in developing new compounds to use as hydrogen storage media. In the present study, the hydrogen uptake characteristics of mechanically alloyed titanium-magnesium-nickel have been studied. Thermal and composition data obtained for studies carried out using three different ball-to-powder ratios by mass are presented in a discussion of the hydriding properties of mechanically alloyed Ti-Mg-Ni. It was found that up to 11 wt% hydrogen was obtained for a Ti-Mg-Ni mixture that was ball milled at a ball-to-powder ratio by mass of 70:1. (C) 2002 International Association for Hydrogen Energy. Published by Elsevier Science Ltd. All rights reserved.