Disease is a natural part of every crop production system. This is true for every crop species and for each type of production system; irrigated versus rain-fed, conventional versus reduced tillage, and continuous versus rotation cropping. Disease management is important for producing acceptable yield and quality of cruciferous crops such as cabbage, cauliflower, canola, rutabaga, grown for the fresh market, the processor, and for storage. Diseases caused by viruses, bacteria, and fungi, as well as physiological disorders, are all found in cruciferous crops in Ontario. This Factsheet discusses the biology, recognition, and management of diseases of crucifers caused by fungi. Graduating students, researchers and teachers desirous of updating the information on different aspects of the diseases caused by them, will find this bookto be useful.