In response to the introduction and rapid spread of soybean aphid, farmers in the Upper Midwest were surveyed about their treatment of and knowledge about soybean aphids for crop years 2004, 2005, 2006, and 2007. Overall, the farmers showed a fairly good understanding of soybean aphids and their impact on soybeans. Over 80% said soybean aphids could be treated and repopulate in the same crop year. For 2004-2006, at least 75% of the farmers said aphids damaged their soybeans by sucking sap. However this percentage dropped to 59% for 2007 with a greater percentage pointing at a combination of damage methods. This lower percentage for 2007 may be due to a broader, randomly selected sample of farmers who received the surveys by mail versus farmers who attended meetings in the first three years. However, even though fewer seemed to have a clear understanding of how aphids damage soybeans, other measures indicate a stable or improved understanding of soybean aphid biology and control. Over 70% said the frequency with which aphids should be treated for profitable control depends on aphid counts, weather conditions and plant growth stage. About a third of the farmers believed that aphids inflict the most damage during early flowering through pod set (R1-R3); however, about a third also thought aphids could inflict the most damage at any stage. Over half the farmers considered the lowest aphid density for profitable aphid control to be 250 aphids per plant. Over 80% said scouting reports were very important for making a decision to treat for aphids; over half the farmers said plant growth stage was also very important.