Several arylhydroxamic acids were synthesized, characterized and tested as collectors in the flotation of a Cu-Zn sulphide ore. Arylhydroxamic acids floated copper in preference to iron and zinc minerals. Substitution in the N-phenyl ring increased the efficiency of the collector. However, increase in alkyl-chain beyond C-6 in the acyl group decreased the flotation efficiency of the collector. N-butanoylphenylhydroxylamine was found to give the best result and floated about 93 wt% of Cu in about 32 wt% of the feed taken and the collector usage was only about 70 g per tonne of the ore. Pyrite flotation was minimum at pH 11.