Studies on the effect of the structural and compositional properties of layered double hydroxides (LDHs) and their decomposition products on the ethanolysis of propylene oxide to form glycol ethers are reported. The reaction, supported by results of indicator titrations, is used as a tool for elucidating the identity of the active sites in these materials. For LDHs, the catalytic behavior relates to their structural properties and the active sites can therefore be rationalized. In the case of their calcined derivatives, however, there is no apparent correlation due to the diversity of the active sites.