22 April is marked by the UN as International Mother Earth Day and in many countries as just Earth Day. The International Day recognizes how the Earth and its ecosystems provide its inhabitants with life and sustenance. It also recognizes a collective responsibility, as called for in the 1992 Rio Declaration, to promote harmony with nature and the Earth to achieve a just balance among the economic, social and environmental needs of present and future generations of humanity. To help commemorate International Mother Earth Day, United Nations Secretary-General Ban Ki-moon told "Dialogue on Harmony with Nature" that, "I have made sustainable development an overarching priority for the United Nations because this is the most fundamental challenge facing our world. On this International Day, let us renew our pledges to honour and respect Mother Earth. This is critical as we work to achieve the Millennium Development Goals – to improve living conditions by the year 2015. And it is essential to setting new targets beyond that date," the Secretary-General said. The theme for this year's International Mother Earth Day is 'The Face of Climate Change.' Last week at the World Bank, the Secretary-General also spoke to partners of the Sustainable Energy for All Initiative saying, "We need to ensure that the benefits of modern energy are available to all, and that energy is provided as cleanly and efficiently as possible."