Passage of an ordinance in 1989 restricting the use of ozone depleting chemicals (ODCs), including chlorofluorocarbons, in Irvine, California was hailed as an effective approach to hastening the repair of the earth's protective ozone layer. Administration of the ordinance has emphasized education and technical assistance over enforcement. Although some companies began reducing ODC use and emissions prior to passage of the ordinance, further reductions in use and a 36 percent reduction in emissions occurred in 1990, the year the ordinance went into effect. Critics of the ordinance contended that the City's action was premature, likely to have adverse consequences on local business, and unenforceable. Evidence is not available to indicate that substantial harm to business occurred. Irvine's experience demonstrates that it is possible for local governments to encourage greater reductions than would otherwise occur with national and international controls.