Odors originating from livestock wastes are often the source of irritation between agricultural producers and rural and suburban neighbors. Because individual tolerance for farm-related odors varies substantially and odor is so difficult to quantify, it is likely to remain an unregulated environmental issue. However, odor is often the problem that draws attention to a farm and can expose other environmental problems more easily quantified and regulated. In addition, odor contributes to an agricultural producer's challenge of maintaining acceptable neighborhood relations.