<P> The United Nations Conference on the Human Environment was held in Stockholm, Sweden from June 5--16 in 1972 . </P> <P> When the United Nations General Assembly decided to convene the 1972 Stockholm Conference, at the initiative of the Government of Sweden to host it, UN Secretary - General U Thant invited Maurice Strong to lead it as Secretary - General of the Conference, as the Canadian diplomat (under Pierre Trudeau) had initiated and already worked for over two years on the project . </P> <P> Sweden first suggested to the United Nations Economic and Social Council ECOSOC in 1968 the idea of having a UN conference to focus on human interactions with the environment . ECOSOC passed resolution 1346 supporting the idea . General Assembly Resolution 2398 in 1969 decided to convene a conference in 1972 and mandated a set of reports from the UN secretary - general suggesting that the conference focus on "stimulating and providing guidelines for action by national government and international organizations" facing environmental issues . Preparations for the conference were extensive, lasting 4 years, including 115 governments, and costing over $30,000,000 . </P> <P> The Soviet Union and other Warsaw Pact nations boycotted the conference due to the lack of inclusion of East Germany, which was not allowed to participate as it was not a full member of the UN . </P>

1972 declaration of the united nations conference on the human environment