Since its creation in 1972, UNEP has monitored the state of the environment, informed policymaking with science and coordinated global responses to environmental challenges. Its work has been made possible by the dedication and commitment of its staff, combined with strong leadership vision and member state support. UNEP is headed by an Executive-Director at the Under-Secretary-General level. Thus far, eight leaders have held the role from a variety of backgrounds, including public service, private sector, nongovernmental, science and policymaker backgrounds. Executive-Directors are appointed by and report to the United Nations Secretary-General.