The reaction of Co(II) with 5,15-dipyridyl-10,20-diphenylporphyrin (H(2)DPyP) produces the first metal-organic coordination polymer supported by a trans meso-bifunctional porphyrin ligand. Formulated empirically as [Co(3)(DPyP)(3)] x 4DMF, this compound exhibits a ribbonlike coordination network consisting of tetranuclear metalloporphyrin cages. The DMF guest molecules fill the intra-ribbon cages as well as the inter-ribbon space. Evacuation of [Co(3)(DPyP)(3)] x 4DMF at 130 degrees C generates [Co(3)(DPyP)(3)] that retains crystallinity, as shown by its powder X-ray diffraction pattern, which is consistent with that of [Co(3)(DPyP)(3)] x 4DMF.