The focus in this study is on preparing hydrotalcite (HT) thin micromembranes and on understanding their transport characteristics. HT micromembranes were prepared on silicon wafers and on perforated stainless steel discs, using two different types of HT colloidal suspensions, and were characterized by various surface techniques, as well as with single-gas permeation tests. Electron microscopy indicates that the HT films are compact and dense, and well-adhering on the substrates. For the Si-based membranes, the presence of an intermediate gamma-Al2O3 layer seemed to improve the characteristics of the deposited HT Films. The study of the permeation properties of the HT micromembranes indicated ideal separation factors that exceeded the corresponding Knudsen values. Some of these membranes were also permselective towards CO2. These HT micromembranes show good promise for application in sensor devices and in membrane microreactors. (c) 2009 Elsevier Ltd. All rights reserved.