Wheat stem rust also called black stem rust caused by Puccinia graminis f. sp. tritici is amongst the biotic catastrophic diseases because of its ability to cause complete annihilation of wheat crops over wide areas during epidemic years. The East African highlands in general and Ethiopia in particular is considered as a hot spot area for the development of stem rust complex. The high virulence diversity and evolution rate of the pathogen (like race Ug99) makes a considerable proportion wheat germplasm at risk. This book provides an overview of the significance of wheat stem rust, the...