In the 1950s and early 1960s, stem canker was the most important soybean disease and slowed the expansion of soybean acres in the Midwest. Highly susceptible soybean varieties were discontinued and replaced by varieties less susceptible or moderately resistant to stem canker. Stem canker is regarded as a warm temperature disease and thus the climate of Wisconsin has been regarded as less conducive for stem canker. However, symptoms typical or suggestive of stem canker have increased in frequency since the late 1990’s. Stem canker was observed commonly in 2003 and 2005 in Wisconsin, but was less prevalent in 2004. Stem canker is regarded as part of a stem disease complex that also includes white mold (Sclerotinia stem rot) and brown stem rot. While white mold is often very obvious, brown stem rot and stem canker are often overlooked or confused with stress related to climatic conditions or with seasonal changes in soybean growth and development. If considered as a complex, brown stem rot, white mold and stem canker occur across a range of climatic conditions that essentially ensure a high probability that one of them will be yield-limiting in a given year. Thus, the ideal soybean variety would have resistance to each disease.