Equimolar and excess ratio reactions of AlMe(3) and Al(i)Bu(3) with the ligands 4,5-(P(E)Ph(2))(2)tzH (tz = 1,2,3-triazole; E = O (1), S (2), Se(3)) were performed, showing a vast variety of coordination modes. The products obtained, [AlR(2){kappa(2)-O,O'-[4,5-(P(O)Ph(2))(2)tz]}] (R = Me (4), (i)Bu (5)), [AlR(2){kappa(3)-N,N',S-[4,5-(P(S)Ph(2))(2)tz]}(mu-tz)](2) (R = Me (6), R = (i)Bu (7)), [AlMe(2){kappa(2)-N,Se-[4,5-(P(Se)Ph(2))(2)tz]}] (8), [Al{kappa(2)-N,Se-[4,5-(P(Se)Ph(2))(2)tz]}(3)] (9), [AlR(2){kappa(2)-O,O'-[4,5-(P(O)Ph(2))(2)tz]}-(N'-AlR(3))] (R = Me (10), (i)Bu (11)), and [AlR(2){kappa(2)-N,S-[4,5-(P(S)Ph(2))(2)tz]}-(N'-AlR(3))] (R = Me (12), R = (i)Bu (13)), were characterized by spectroscopic methods, and the structures of 1, 4, 6, 7, 9, 10, and 12 were obtained through X-ray diffraction studies. Theoretical calculations were performed on the deprotonated ligands and on selected compounds to obtain information regarding the coordination variety observed for these compounds.