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In context of investigations of doped sodium alanate as a hydrogen storage material, an investigation combining a TEM-EDX study and XAFS measurements has been carried out on doped sodium alanate, using titanium tetrabutylate (Ti(OBu n ) 4 ), colloidal titanium nanoparticles (Ti*) or TiCl 3 as doping agents. It was found that the dehydrogenated wet-chemically Ti(OBu n ) 4 doped NaAlH 4 consists of a crystalline Al and an amorphous NaH phase. The striking result of EDX analyses is that in each case the Ti-dopant is found to be present only in the Al phase. On the other hand, dehydrogenated NaAlH 4 doped with Ti* or TiCl 3 via ball milling is an amorphous material, with diffuse boundaries between Al and NaH phases and a highly uniform distribution of titanium in the Al-phase. Both the use of the ball milling doping method and of Ti* nanoparticles as dopants, are probable reasons for the outstanding kinetics of the Ti* doped material (B.