P-50 oxime dissolved in Escaid 100 has been shown to extract ruthenium from aqueous nitrate-nitric acid solutions in which the metal exists as a range of complex species. Rates of extraction were low, but increased with increasing acid concentration (k(f) = 6.82 x 10(-3) min(-1) in 4 mol.dm(-3) nitric acid). Distribution ratio values ranged between 0.95 and 1.7, and the ruthenium remaining in the raffinate consisted mainly of anionic species. It was shown that by careful control of the conditions of extraction and stripping, it was possible to selectively extract and separate palladium from ruthenium and rhodium in nitrate solutions.