Almost every material, including human beings, are either oxides or hydroxides at their surface. Despite this, our understanding of oxide surfaces is relatively primitive. There are many reasons for this, ranging from the limitations of many conventional methods for insulators, the complications of understanding scanning probe images of surfaces, errors in density functional methods used to help understand experimental results as well as oversimplifications as to what oxide surface structures are.
While it has often been thought that the surfaces of oxides are simple, in many cases they are not and can be far more complex than those of semiconductors and metals. Over the last decade there has been substantial progress and we are now starting to understand many of the forces that determine their structure. This talk will provide an overview of both older and very new work experimental and theoretical work, tracing the understanding from earlier concepts such as polarity to better analyses in terms of local bonding of polyhedral structures to some very recent work based upon dealing with oxide surfaces as partially ordered with both enthalpy and entropy terms being important.