42nd Leeds-Lyon Symposium on Tribology 2015 Special Issue: Surfaces and Interfaces, mysteries at different scales

The 42nd edition of the International Leeds-Lyon Symposium on Tribology took place at the conference facilities of the Valpré Hotel (Ecully, France), 7–9 September 2015. This year the conference location was chosen to allow attendees the possibility of living accommodation on site. This option facilitates both scientific and personal exchange between the participants. This symposium edition also celebrated the 50th anniversary of the publication of the classical paper by Greenwood and Williamson, which first described the mechanics of contact between rough deformable surfaces. This 42nd Leeds-Lyon Symposium was a scientific and participative success, carrying on the tradition of a warm and friendly conference atmosphere, which has been its reputation since the inception.