The syntheses of the dinucleating bisbidentate ligand bis[5-(l-methyl-2-(6'-methyl-2'-pyridyl)benzimidazolyl)]methane (bismbmp, 3) and its mononuclear analogue 6-methyl-2-( 1 -methylbenzimidazol-2-yl)pyridine (mbmp, 1) are reported. The ligand mbmp (1) reacts with copper(I) to give [Cu(mbmp)₂]ClO₄ whose crystal structure (CuC₂₈H₂₆N₆ClO₄, z = 7.877 (1) Å, b = 13.810 (2) Å, c = 25.090 (7) Å, ß = 95.29 (1)°, monoclinic, P2₁/c, Z = 4) shows a mononuclear structure with Cu(I) pseudotetrahedrally coordinated by two bidentate , '-diimine donor groups. The same chromophore is found for each copper ion in the dinuclear complex [Cu₂(bismbmp)₂](ClO₄)₂-H₂0 obtained by reaction of copper(I) with bismbmp. Conductivity measurements and UV-visible spectra show that the dinuclear structure is maintained in solution in polar aprotic solvents, and ¹H-NMR measurements unambigously establish a double-helical structure for this complex. Mbmp reacts with cobalt(II) to give octahedral [Co(mbmp)₃] (ClO₄)₂-CH₃CN. The same coordination sphere is obtained when bismbmp reacts with cobalt(II), to give the triple-helical dinuclear complex [Co₂(bismbmp)₃] (ClO₄)₄-3H₂0, selectively produced by self-assembly. Spectroscopic results show that the triple-helical structure (D} symmetry) observed in the solid state is maintained in polar aprotic solvents. Spectrophotometric titrations show that bismbmp reacts with zinc(II) to give successively a triple-helical complex [Zn₂₋ (bismbmp)₃]⁴⁺, a double-helical complex [Zn₂(bismbmp)₂]⁴⁺, and a third complex [Zn₃(bismbmp)₂]⁶⁺. The influence of metal ion stereochemical preferences on the self-assembly of dinuclear helical complexes is discussed.