Nitrilotrismethylenetri-2-pyridinium perchlorate, C18H21N4(3+).3C1O4-, Mr = 591.74, cubic, P2(1)3, a = 13.289 (3) A, V = 2347 (2) A 3, Z = 4, Dx = 1.675 (2) g cm-3, lambda(Mo K alpha) = 0.71069 A, mu = 4.60 cm-1, F(000) = 1216, T = 189 (3) K, R = 0.056 for 1073 unique observed reflections with I greater than sigma(I). All four ions lie on threefold axes. The perchlorate ions are nearly regular tetrahedra. The bond lengths and angles in the ions are normal. As the name implies, the cation is protonated on the pyridine N atoms and not on the amine N atom. Each H atom attached to an N atom is part of a three-centered hydrogen bond in which the H-atom acceptors are O atoms on two different perchlorate ions.