We have characterised the WO3T'iO2 (anatase) catalyst system using High Resolution Electron Microscopy. We will show that the overlayer preserves the surface roughness of titania and consists of 2D-hexagonal clusters that have a definite orientation relationship with the support. The contrast observed from these clusters is discussed in terms of existing structural models. A comparison between traditional chemical methods of preparation and simple mechanical mixing is made to assess the effectiveness of the latter to disperse WO3.