The Montreal Protocol on Substances that Deplete the OzoneLayer is a landmark international agreement designed to protect the stratospheric ozone layer. The treaty was originally signed in1987 and substantially amended in 1990 and 1992. The Montreal Protocol stipulates that the production and consumption of com-pounds that deplete ozone in the stratosphere (chlorofluorocar-bons - CFCs, halons, carbon tetrachloride, and methyl chloroform) were to be phased out by 2000 (2005 for methyl chloroform).