Sudden death syndrome (SDS) is a mid- to late-season, soil borne disease that occurs primarily in soybean fields with high yield potential. First observed in Arkansas in 1971, SDS now causes significant losses in Midwestern states such as Illinois and Indiana and is considered the most important fungal disease in causing yield loss in the North Central Region. The disease was first noticed in Iowa in 1993. Now the disease has been found from border to border in Iowa. It occurs annually in eastern Iowa and epidemics occur frequently in recent years. Yield losses due to SDS vary widely. SDS may cause premature defoliation in the fall resulting in nearly total yield loss in all or portions of the severely affected fields, depending on the weather in the growing season. The disease causes foliar symptoms, resulting in pod abortion and yield loss up to 70% in severe cases.