This book is intended as a companion volume to the Dictionary of the Fungi. It will portray the immense diversity of the Kingdom Fungi and other groups traditionally regarded as fungi, and present the formal classification adopted in the Dictionary for the non-specialist in systematics. Basic information will be provided for all currently recognized families, and around 250 key families will be described and illustrated in full colour. Notes on ecology, distribution, economic significance and phylogeny will be provided, along with key references. An introduction will set the scene by presenting the overall classification, an overview of morphological structures etc. The book will bridge the gap between the formal presentation of the Dictionary and popular guides to fungi that provide a restricted view of fungal diversity.