This volume is a collection of lectures presented during the 2009 International School on High-pressure Crystal- graphy, which took place at the Ettore Majorana Center for Scientific Culture, between June 4 and 14, 2009, in the very picturesque Sicilian town of Erice. st The 2009 school was the 41 course of the International School of Cryst- lography organized at the Majorana Center and was directed by Elena Figure 1. Audience, including local Boldyreva (Novosibirsk University) organizers (orange scarfs) and student and Przemyslaw Dera (University of participants during one of the lectures....