It is with great pleasure that we present this completely revised English edition of our book How Does MRI Work? An Introduction to the Physics and Function of Magnetic Resonance Imaging only two years after publication of the first English edition. We are particularly pleased that our introductory textbook met with great approval in the English-speaking world and not just in the German-speaking countries. This success has been an enormous incentive for us to further improve and update the text. For this reason, we are now presenting a second edition. All chapters have been thoroughly revised and updated to include the latest developments in the ever-changing field of MRI.