Following a number of traditional scientific meetings organized by us since 1992 in several locations throughout Italy Modena, Gargnano, Pisa, Trento, Frascati, Milano, Alessandria, and Martina Franca , the 2008 Workshop on X-ray Diffraction of Polycrystalline Materials was given a more international flavour. It was jointly organized in Switzerland Villigen by the Italian and Swiss Crystallographic Societies, and by the Paul Scherrer Institute PSI , on 18–22 June 2008. To the best of our knowledge, this has been the first hands-on workshop combining theory, hands-on experimental sessions at both a synchrotron radiation facility SLS and an X-ray powder diffraction laboratory, and hands-on tutorials on structural solution using various computer programs. In order to maintain a high teacher-to-student ratio, we limited the participant number to a maximum of 46. Of these, 22 regular participants were accepted with the first-come-firstserved basis, while the remaining 24 received either partial or total in a few cases financial support. The grants were assigned according to merit, pertinence to on-going research subjects, nationality, age, and chronology of registration. More than 130 people registered and/or informally applied even after the closure of the registrations. Lectures were typically given in the morning sessions with the entire audience in the main lecture room; tutorials experimental sessions and data analyses were given in the afternoons in smaller groups. A vast set of polycrystalline compounds with progressive complexity included those preselected by the school instructors synchrotron radiation and laboratory X-ray measurements were performed on these samples prior to the school , compounds selected during the hands-on session, as well as those brought in by students. Data analyses were performed during the hands-on computer tutorial sessions in the afternoons. A minimum of three teachers or tutors were present in each room. In the first day, Prof. Burgi and Prof. Rius introduced the basics of diffraction and of the powder method. In the next morning, Prof. Masciocchi, Dr. Guagliardi, and Dr. Gozzo illustrated laboratory and synchrotron radiation experimental setups, sample preparation techniques, and basics of profile analysis. In the following days, specific sessions were given about the Rietveld method and the structure solution process, from indexing to direct space and reciprocal space methods of solution, with particular emphasis on new computational techniques and solution of difficult cases Prof. Cerny, Dr. Rodriguez-Carvajal, Dr. David, Dr. Hinrichsen . During the last day, complementary applications of neutron diffraction, synchrotron radiation, and X-ray diffraction were illustrated in the presentations of Dr. Sheptyakov and Dr. Pomjakushin. Finally, applications of XRD in drug development and formulation were presented by Prof. Finney. Data analysis programs, such as EXPO Dr. Altomare and Dr. Rizzi , TOPAS Dr. Hinrichsen and Dr. Galli , FOX Prof. Cerny , and FULLPROF Dr. Rodriguez-Carvajal , were widely employed during the afternoon sessions, with the students subdivided into small groups. Presentation of ICDD activities and products was also included in the School program.