Layered double hydroxides (LDHs) containing cadmium as the divalent metal and aluminium as the trivalent metal have been prepared by coprecipitation from a mixed metal nitrate solution, and were obtained with nitrate and carbonate as the counter anions, and as single crystalline phases. XRD patterns show that these LDHs are isostructural with synthetic hydrotalcite, with interlayer spacings of 8.24 and 7.54 Å for Cd/Al/NO ₃ and Cd/Al/CO ₃ LDHs, respectively. These compounds were intercalated with phenylphosphonic acid (PPA) and 2-carboxyethylphosphonic acid (CEPA). Intercalation is confirmed by XRD, where increased interlayer spacings were observed for the intercalation compounds. Interlayer distances of 14.59 Å were observed for the PPA intercalation compounds, independent of the original counter anion. CEPA intercalated LDHs present interlayer spacings of 11.74 Å for Cd/Al/CEPA obtained from Cd/Al/NO ₃ LDH and a double interlayer distance of 11.35 and 12.21 Å for Cd/Al/CEPA obtained from Cd/Al/CO ₃ LDH. IR and NMR measurements suggest that this double interlayer spacing is due to the interaction of CEPA to the layers through both of its extremities, i.e. a phosphonate and a carboxylate interaction.