In 2007, International Ozone Day was celebrated for the 20th anniversary of the signing of the Montreal Protocol. On 19 Dec 1994, the United Nations General Assembly proclaimed 16 Sep to be the International Day for the Protection of the Ozone Layer, commemorating every year the signing of the Montreal Protocol on 16 Sep 1987, in Montreal, Canada. This landmark event to protect the stratospheric ozone layer is one of the most successful international treaties. By 2007, 191 countries had signed the protocol, under which there was to be a phase out of the production and consumption of ozone depleting chemicals. For 2007, The Drummers and A Kid's Dream videos were made available as Public Service Announcements for TV and new educational materials were prepared. The Montreal Protocol: Celebrating 20 Years of Environmental Progress..., by Donald Kaniaru. - book suggestion.