This 2.5-day practical workshop on sample preparation for single particle cryo-EM, jointly organised by the ESRF, EMBL Grenoble, ILL and the IBS, will be held from 23rd to 25th May, 2023. This is the fifth of a series of practical hand-on workshops and is aimed at PhDs, PostDocs and scientists new to the field of single particle cryo-EM. During the course, participants will learn theoretical and practical aspects of sample preparation for single particle cryo-EM including prior quality control by negative staining. The participants will also learn on quality assessment of the grids prepared by them.