The Northwestern Illinois Agricultural Research and Demonstration Center is a facility located near Monmouth in Warren County.

Since its establishment in 1980, the Northwestern Illinois Agricultural R&D Center has been dedicated to conducting meaningful research on soil chemistry and fertility, soil management, crop production, weed science, entomology, plant pathology, pest management, and environmental quality. The work of the Northwester Illinois Agricultural R&D Center seeks to improve agriculture in Northwestern Illinois by providing farmers with valuable information and data.