This book aims to describe, though in a quite light way, the social role of plant diseases, letting the reader know the topical importance of plant pathology, as well as the role of plant pathologists in our society. Plant diseases caused, in the past, significant economic losses, deaths, famine, wars, and migration. Some of them marked the history of entire countries. One example among many: the potato late blight in Ireland in 1845. Today plant diseases are still the cause of deaths, often silent, in developing countries, and relevant economic losses in the industrialized ones. This book, written with much passion, neither wants to be a plant pathology text. On the contrary, it wants to describe, in simple words, often enriched by the author's personal experience, various plant diseases that, in different times and countries, did cause severe losses and damages. Besides the so-called "historical plant diseases", in the process of writing this book, she wanted to describe also some diseases that, though not causing famine or billions of losses, because of their peculiarity, might be of interest for the readers. Thus, this book has not been conceived and written for experts, but for a broader audience, of different ages, willing to learn more about plant health and to understand the reasons why so many people in the past and nowadays choose to be plant pathologists. This is because plants produce most of the food that we consume, that we expect to be healthy and safe, and because plants make the world beautiful. The title "Spores" is evocative of the reproduction mean of fungi. Spores are small, light structures, often moving fast. The chapters of this book are short and concise. Just like spores!