High-spin Ni(II) complexes of the linear pentadentate ligand 2,6-bis([2'-aminophenylthio]methyl)pyridine (Batp) and the tridentate ligands ([2'-aminophenylthio]ethyl)pyridine (Atep) 1,5-bis(N-methylbenzimidazol-2'-yl)-3-oxapentane (Mbeo) have been prepared. Crystal structures of the complexes [Ni(Batp)(H 2 O)](CF 3 SO 3 ) 2 (2) and [Ni(Atep) 2 ](ClO 4 ) 2 (4) reveal pseudooctahedral coordination. Tetragonal distortion in [Ni(Mbeo) 2 ](ClO 4 ) 2 (5) is evident from the longer Ni-O and shorter Ni-N bond lengths. From the electronic spectrum of 5, the tetragonal distortion parameter D t and the in-plane Dq x y and axial Dq z ligand field parameters are calculated. The three Ni(II) complexes exhibit irreversible cathodic electrochemistry.