Environment A Breath of Fresh Air

Delegates of 24 nations sign a historic pact on ozone

To paraphrase that famous remark about the weather, everyone talks about the ozone layer, but no one does anything about it. Though evidence has mounted that man-made compounds called chlorofluorocarbons (CFCs) are destroying the screen of ozone-enriched air that helps shield the earth from the sun's dangerous radiation, the world's nations have been slow to develop a consensus on how to cope with the problem.

Last week the world, or at least a part of it, finally did something. At a conference in Montreal sponsored by the United Nations Environment Program, 24 countries signed a milestone accord that promised to halve...