Nitrogen containing carbon nanotubes have been synthesized using a variety of templates. The hydrogen absorption capacity of these materials has been evaluated. The study shows that it is necessary to stabilize nitrogen in the carbon nanotube framework for reproducible hydrogen uptake. The role of nitrogen is to activate gaseous molecular hydrogen and its subsequent transport to the carbon surface by "spill-over" process. Nitrogen sites, in addition to its catalytic role, can also contribute to net hydrogen storage.