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Investigations on selected oxidation hair dyes - which are normally applied in the form of gels and pastes - have shown that it is possible to use these dyes on wool in commercial wool dyeing procedure. The precursors are applied at low low temperatures (e.g. 60oC) and short treatment times (20 min). For the subsequent oxidation with H2O2 temperatures of 40oC are sufficient together with a development time of 40 min. Therefore, this colouring method offers a genuine low temperature colouring potential for wool, saving energy and time with a significant improvement of the wool quality in comparison to commercial wool dying at substantially higher temperatures (98oC). At the same time the oxidation hair dyes offer a substitution potential for the heavymetalliferous chrome colouring dyes, since they are free from toxicological alarming heavy metals. With the system 2,5-diaminotoluene sulfate/2-amino-4-hydroxyethyl aminoanisole sulfate a black coloured wool could nearly be realized. The use of 4 % oww precursor and a dye bath exhaustion up to 96 % results in a deep blue-black coloured wool. The small molecule size of the resulting chromophor together with its good water solubility turned out as a disadvantage for the fastness. With the system 1,10-bis-(2,5-diaminophenyl)-1,4,7,10-tetraoxadecane/1,3-bis-(2,4-di-aminophenoxy)propane a deep dark-blue black colour could be achieved. The structure of the high-molecular oligomers of this dye could not be determined. Investigations on the sorption of the precursors 1,10-bis-(2,5-diamino-phenyl)-1,4,7,10-tetraoxadecane and 1,3-bis-(2,4-di-aminophenoxy)propane on wool showed that the bath exhaustion of the precursor can be increased significantly from 60 to over 85% by addition of surfactants such as sodiumdodecyl sulfate or dodecylbenzene sulfonic acid or by the use of plasma-treated wool. The alkaline fastness to perspiration with values of 3-4 and the (dry/wet) fastness to rubbing with values of 4 and 3-4 are satisfactory. The requirements of the Wollmark spezification for fabrics are almost met. The fastness to light with values of 4 fulfills the minimum requirements of the Wollmark federation for fabrics.