The detection of natural gas leakage has long been a concern to the natural gas industry, but never more so than today. Increased public awareness of safety and huge increases in the cost of product liability litigation has resulted in a greater focus on gas odorization. While it must be recognized that no odorant will be 100% effective in warning of the presence of natural gas, basic knowledge about the properties and characteristics of odorants used for natural gas and an understanding about some of the potential problems in the odorization of such gas can be extremely helpful for those involved in the gas odorization process