It takes two: The complementary sulfate and guanidinium ions in [C(NH 2)3] [N(CH3)4][SO4] both act as 3-connecting nodes to give a 3D hydrogen-bonded network with the chiral (10,3)-a topology (see X-ray crystal structure; O red, S yellow, H pink, N blue, C black). In contrast, the 3-connected hydrogen-bonded network in the much-studied guanidinium sulfonates is 2D.