The utility of the pyrazole-carboxylate mixed ligand system has been probed with the synthesis of five new coordination polymers, derived from bis-pyrazole ligand 4,4'-methylenebis(3,5-dimethyl-1H-pyrazole) H(2)L1, large semirigid dicarboxylate coligands, and the deliberately designed and synthesized ligand para-((3,5-dimethyl-1H-pyrazol-4-yl)methylene)benzoic acid H(2)L4. Complex poly-[Co(H(2)L1)(L2)(OH2)].1/2H2O 1 features the coligand (S,S)-1,4,5,8-naphthalenetetracarboxylic diimide-N,N'-bis(2-propionate) L2, and comprises chiral two-dimensional sheets, associating via substantial pp stacking interactions. Complexes 2 and 3 contain the coligand 1,4-bis((3-carboxyphenyl)methyl)piperazine L3. Complex poly-[Co(H(2)L1)(2)(L3)] 2 is a two-dimensional polymer containing octahedral Co(II) ions, whereas modifying the synthesis conditions gave complex poly-[Co2(HL1)(2)(L3)] 3, a three-dimensional a-Po structure containing pyrazolate-bridged dimers of tetrahedral Co(II) ions, displaying weak antiferromagnetic coupling. Magnetic data for complex 3 fitted well to a S = 3/2 Heisenberg (-2JS1.S2) dimer model with J = -3.2 cm1 and g = 2.25. We then prepared the new heteroditopic ligand para-((3,5-dimethyl-1H-pyrazol-4-yl)methylene)-benzoic acid H(2)L4, and the complexes poly-[Co(HL4)(2)].H2O 4 and poly-[Cu(HL4)(2)].2MeOH 5, which demonstrate for the first time the tendency of flexible pyrazole-carboxylate coordination polymers with perfectly commensurate linker dimensions to lead to low-dimensional assemblies. These results give fresh insight into the structural properties of flexible bispyrazole-carboxylic acid systems as a function of coligand dimensions, and provide new directions for designed polymeric cluster compounds.