We report the first observation of the complete quenching of the Hall effect in a one-dimensional conductor. In our narrowest wires at low temperatures and for small magnetic fields, where the 1D subband splittings exceed both kBT and ℏωc, we observe striking departures from the 2D Hall effect, characterized by an unexpected low-field plateau and a precipitous, complete suppression of the Hall resistance. We believe these to be unambiguous manifestations of one-dimensional electrical transport; they appear to provide a direct measure of the number of quantum conduction channels that participate