The complex formation between the Fe(3+) ion and 2-hydroxybenzohydroxamic acid (salicylhydroxamic acid, H(2)L) has been Studied at 25 degrees C in 1.0 mol.dm(-3) (Na)ClO(4) medium by potentiometric titrations with redox Fe(3+)/Fe(2+) and/or glass electrodes. On account of precipitation of Fe(II)-salicylhydroxamates, the redox half-cell was employed only in measuremenrts at [H(+)] > 3- 10(-3) mol.dm(-3). The redox and glass electrode data, collected ill the concentration ranges (mol.dm(-3)) 1.10(-3) <= [Fe(III)] <= 5.10(-3), 0 [H(2)L](tot) <= 0.015, and 0.1 >= [H(+)] >= 10(-2), are consistent with the presence of the species FeHL(2+) and Fe(HL)(2)(+). Glass electrode measurements, in solutions where (10(-1.5) >= [H(+)] >= 10(-4)) mol.dm(-3), (3.10(-4) <= [Fe(III)] <= 7.10(-3)) mol.dm(-3), and (1 <= [H(2)L](tot)/[Fe(III)] <= 3) mol.dm(-3), are explained by assuming in addition to FeHL(2+) and Fe(HL)(2)(+) the complexes FeL(2)(-) and Fe(5)(HL)(5)(OH)(8)(2+). The pentamer is probably a derivative of the hypothetical hydrolytic complex, Fe(5)(CH)(8)(7+). Stability constants for their formation in 1 M NaClO(4) as well as in dilute solution are reported.