It has cost HK$29 billion over 10 years so far, but the average person on the street may well be wondering if the campaign to clear the air has made much difference.
An estimate by the South China Morning Post found that this is the amount already footed by taxpayers and businesses, directly or indirectly.
The result? About 84,000 tonnes of four major pollutants - sulphur dioxide, nitrogen oxides, nitrogen dioxide and respirable suspended particles - removed from the air at an average cost of HK$34,523 per tonne.
Businesses that have made investments such as power firms and franchised bus operators believe the money was well spent, but critics say the improvement is nowhere near enough. Other pollutants are on the rise and visibility has deteriorated.
The HK$29 billion price tag accounts for most major initiatives since 2000. These include direct subsidies and tax concessions offered by the government, capital expenditure by private firms to meet public policy, and legal changes implemented to fight air pollution.
It does not include recurrent spending to keep the clean-up measures going or expenditure by the franchised bus companies, which could not give an estimate, on the amount spent to retrofit thousands of old buses with cleaner technology.
It also excludes the roughly HK$16 billion in tangible economic loss and health costs related to air pollution since 2004, based on the Hedley Index that tracks the impact of air pollution almost on a real-time basis.