This chapter gives an overview of the current preparation strategies for the synthesis of bulk and supported metal oxide catalysts, in order to give rational guides to understand the synthetic challenges associated with the preparation of these catalytic systems developed in the successive chapters. Bulk and mixed oxides syntheses for catalysis are reviewed with a presentation of the main synthesis strategies and of novel routes implemented, with a focus on the control of the textural properties of the materials for simple oxides and on two classes of mixed oxides: perovskites and hexaaluminates, that are particularly interesting for high temperature reactions. The final section concentrates on the synthesis of supported metal oxide catalysts, with a particular emphasis on the discussion of the interfacial chemistry occurring at the solid–liquid interface during the first steps of the deposition of an active oxide phase on a high-surface area support.