Surface-grafted polymer brushes are a very attractive class of boundary lubricants. This article presents an overview of the tribological properties of surface-attached synthetic polymers. After a brief review of some mechanistic considerations and a discussion of tribological characterization tools, the lubrication properties of the three main classes of surface-attached polymer brushes, viz. (i) hydrophilic, (ii) hydrophobic and (iii) fluorinated brushes, will be presented. The article concludes with a brief discussion of possible applications of polymer brush-based lubricants.