Crystal structure of a material is sometimes the most important factor to determine its physicochemical properties. X-ray, electron and neutron diffractions are the most powerful methods for elucidating full 3D structures from single crystals and microcrystalline powder samples. This course provides an overview of crystal structures of materials, a theoretical basis and practical exercises to the structure identification, analysis and determination processes: the fundamental principles that underlie crystallographic practice, and hands-on experience of experimental and computational aspects of structure determination. Methods with single crystals as well as powder samples will be covered including Rietveld refinement techniques. At the end of the course, students are expected to analyze and solve structures with experimental data, and will be ready to begin to tackle crystallographic problems for their own areas of research whichever involves any kind of solid crystalline material.