The interaction of three equivalents of methyl-lithium with tungsten hexachloride in diethyl ether gives a brown solution from which hexamethyltungsten can be isolated. The chemical and spectroscopic properties of the compound are described. Reaction with nitric oxide gives tetramethylbis(N-methyl-N-nitrosohydroxylaminato)tungsten(VI) which is shown by n.m.r. studies to be stereochemically non-rigid at room temperature.