In subsequent years the production and consumption of ozone-depleting substances (ODS) have been rapidly and worldwide reduced in order to fulfill the conditions in the Montreal Protocol (1987). According to economic theory it is more effective to use a market-based system than a regulatory one since the former combines environmental improvements and economic efficiency. A regulatory system will instead cause economic inefficiency. The US is one country that decided to use a market-based tax system in order to replace ODS. The purpose of this thesis is to evaluate the environmental benefits in monetary terms and in terms of reduced cases of negative human health effects caused by the US tax on ODS. Additionally the economic costs and the net result of the tax will be calculated by combining the result of two existing studies. The approximated estimations of the net results of the ODS tax in the US is at least 32.87 billion of 1997 US Dollars. Additionally the tax has lead to at least 2,812 reduced cases of melonama skin cancer, 221 reduced cases of non-melonama skin cancer, 19,006 reduced cases of cataracts and 49 reduced fatalities from skin cancer.