This is a book for the general reader about the world of fungi. We should know more about fungi. They have killed us, saved us and served us since before written records began. We have been making bread, brewing ale, and fermenting wine for millennia. Our crops have been at the mercy of fungal diseases since we became farmers, and they still are. Fungal diseases have caused large demographic changes - from the great plague of 'St. Anthony's Fire' of the Middle Ages (caused by a fungal toxin) to the Irish mass migration to the Americas during the famine (caused by a fungal disease of the potato crop). We can also thank fungi for antibiotics, but do we fully appreciate the revolution in life style (and life expectancy) that these taken-for-granted treatments permit? One of the first people to receive penicillin treatment in England in the 1940s was a policeman in Oxford. He died of septicemia when the supplies of the antibiotic ran out after he had been scratched by a rose thorn. Fungi enabled plants (by a mutualistic combination that persists today) to invade the land during the evolution of life on Earth. Higher fungi are almost unique in their ability to decay the chemical components of timber. Without the wood-rotting fungi we would be up to our eyes in dead trees. Fungi give us the opportunity of treating plant diseases and killing specific weeds, as well as being very useful for cleaning up polluted environments and for producing chemicals. In short, this book will show you why it is wise to look again at fungi and appreciate these extraordinary organisms for what they are: a vital component of our lives and of the Earth's ecosystem.