Introduction to the Rietveld Method 1. The early days: a retrospective view 2. Mathematical aspects of Rietveld refinement 3. The flow of radiation in a polycrystalline material 4. Data collection strategies: fitting the experiment to the need 5. Background modelling in Rietveld analysis 6. Analytical profile fitting of X-ray powder diffraction profiles in Rietveld analysis 7. Crystal imperfection broadening and peak shape in the Rietveld method 8. Bragg reflection profile shape in X-ray powder diffraction patterns 9. Restraints and constraints in Rietveld refinement 10. Rietveld refinement with time-of-flight powder diffraction data from pulsed neutron sources 11. Combined X-ray and neutron Rietveld refinement 12. Rietveld analysis programs Rietan and Premos and special applications 13. Position - constrained and unconstrained powder-pattern-decomposition methods 14. Ab initio structure solutions with powder diffraction data