SAMS-4 is the Fourth International Workshop on Scattering of Atoms and Molecules from Surfaces, which is organized every three years. The main goal of SAMS-4 is to bring together scientists working in the field of atom and molecule surface scattering, stressing the unsolved and challenging problems which need to be addressed in the near future. It will take place in Madrid from 24th to 27th of September 2019 in the Consejo Superior de Investigaciones Científicas (CSIC) Central Campus and our institute is part of the Scientific and Organizing Committees. You can find all the information in the webpage of the meeting.