Three new hybrid organic-inorganic materials Pb3(H2O)2(p-PO3C6H4CO2)2 (2), Pb6(H2O)2(p-PO3C6H4CO2)4 (3), and Pb5(p-PO3C6H4COOH)2(p-PO3C6H4CO2)2 (4) have been synthesized by hydrothermal treatment involving PbII salts and a rigid heterodifunctional precursor 4-phosphonobenzoic acid {p-PO(OH)2C6H4COOH}. The use of 3-phosphonobenzoic acid {m-PO(OH)2C6H4COOH} as another rigid organic precursor is also reported. These two organic building units possess two distinct functional groups (phosphonic acid and carboxylic acid) both having the aptitude to generate chemical bonds with a metallic precursor. The structures of the produced materials have been solved by means of single-crystal X-ray diffraction data. It was observed that the use of the 4-phosphonobenzoic acid produces the hybrids 2, 3, or 4 that possess a layered structure. In these three materials, the inorganic planes are linked together via an organic bridge. For 2, 3 and 4 the understanding of the stacking of the organic molecules within the layer, the influence of the electronic lone pair and the water molecules is discussed.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)