The objective of the 28th Leeds-Lyon Symposium on Tribology was to define current understanding of the science relating to boundary and mixed lubrication and to compare this with the needs of industry in terms of applications. Major advances have been made in recent years in areas such as contact mechanics, wear, elastohydrodynamic lubrication incorporating surface texture, lubricant interactions with surfaces and the experimental interrogation of surface topography, surface films and lubricant film thickness. However, the needs of industry are equally intense with a seemingly relentless drive towards more compact, efficient and durable tribological systems. Boundary and Mixed Lubrication: Science and Applications publishes peer-reviewed papers presented at the 28th Leeds-Lyon Symposium on Tribology. The Keynote address was presented by Professor Koji Kato, Tohoku University, Sendai, Japan under the title "Wear of Boundary or Mixed Lubrication Regimes", which set the scene for the meeting with a review of recent scientific developments with a clear focus on the potential for technological and industrial development.