In the coordination compound poly[diaqua(mu(2)-4,4'-bipyridine)(mu(2)-4-carboxylatocinnamato)nickel(II)], [Ni(C(10)H(6)O(4))(C(10)H(8)N(2))(H(2)O)(2)](n), both the 4-carboxylatocinnamate and 4,4'-bipyridine (4,4'-bpy) ligands act as bidentate bridges, connecting the Ni(II) centres in an octahedral coordination geometry into a two-dimensional (4,4) layer. Each layer polycatenates two other identical layers, thus giving a rare 2D --> 3D polycatenating network (2D and 3D are two- and three-dimensional, respectively), with a mutually parallel arrangement of the layers. The chiral 4,4'-bpy ligands link the Ni(II) centres into chiral chains, thus introducing chirality into the layer and the resulting 3D network.