The invention relates to layered double hydroxide (LDH) materials and in particular to new methods of preparing improved LDH materials which have intercalated active anionic compounds (improved LDH-active anion materials). The improved LDH-active anion materials are characterised by their high degree of robustness, demonstrated by their high Particle Robustness Factor values, and by their ability to retain substantially all of the intercalated active anionic compound, in the absence of ion exchange conditions and/or at pH above 4.