They proposed the ISO 14000 series. These are voluntary instruments and work like the quality standards such as ISO 9000. Such instruments
are another way to encourage improvements
other than international regulations. However,
it means more responsibility for environmental improvement lies with companies.

http://www.ecology.or.jp/isoworld.htm
For latest numbers of companies with environmental management standards.  

Help with ISO 14001 training

The International Organisation for Standardization launched the ISO 14000 series worldwide in 1996.

ISO 14001/4 is the environmental management standard, based on the british Standard 5750. The European Standard EMAS is slightly more stringent and requires public statements.

There have been many other different initiatives, (in detail in Unit 3) including cleaner production, energy reduction, waste minimisation and eco-efficiency also demonstrating business's response to environmental concerns.