The magnetic susceptibilities of iron(111) N-substituted salicylaldimine complexes of types Fe(sal-XR)3, Fe(sal-NR)2X, [Fe(salH-KR)2X]X, (X = Cl, Br), and [Fe(sal-NR)2]2O have been measured over the temperature range 90-300�K.? The mononuclear complexes exhibit normal high-spin (S = 5/2), Curie-Weiss behaviour. The binuclear oxygen-bridged complexes show antiferromagnetic behaviour and the results have been analysed using the spin-spin coupling mechanism. The exchange interaction is found to be independent of the nature of the N-substituent on the Schiff base. It appears that bulk susceptibility measurements alone cannot unambiguously specify the formal spin state of the ferric ion in these binuclear complexes.