The incidence of anthropogenic fires in South America has increased lately, and fire effects on the biodiversity and ecosystem services are of great concern. On the other hand, natural fires have been present in the continent for thousands of years, acting as an evolutionary driver of vegetation and fauna. Therefore, several ecosystems in South America are fire-prone due to their evolutionary history, while those that have not evolved under frequent fires are fire-sensitive. At the same time, as humans increase fire frequency in some environments they try to banish fire from others, and such anthropogenic fire regimes have enormous consequences for biota, ecosystem services and the environment. This book will address the various South American ecosystems that benefit from the presence of fire, but also those that are harmed by fire. The effects of fire on plant and animal biodiversity of the main South American ecosystems will be presented and discussed considering current trends in climate and land use change, bringing understanding about when and how fire should or should not be used to benefit nature and humans. Options for fire planning and management will be highlighted, especially considering the reduction of wildfire risk and the conservation of biodiversity and natural resources. This broad comprehension of the fire issue in South America will support wise decisions by environmental analysts, conservation managers and public policy makers.