Excessive nitrates in surface waters from tile-drained areas have been associated with several health and environmental problems including blue baby syndrome, bladder cancer, non-Hodgkin’s lymphoma, and hypoxia in the Gulf of Mexico. The development of best management practices to reduce nitrate loads from drainage systems has driven much of drainage-related research over the past two decades. However, researchers have taken great care to concentrate on practices that will not adversely affect yields. In this talk information on recent developments in drainage research and how these have been informed by yields, will be presented.