The Intergovernmental Authority on Development (IGAD) is an eight-country trade bloc in Africa. It includes governments from the Horn of Africa, Nile Valley and the African Great Lakes. It is headquartered in Djibouti.

The Intergovernmental Authority on Development was established in 1996. It succeeded the earlier Intergovernmental Authority on Drought and Development (IGADD), a multinational body founded in 1986 by Djibouti, Ethiopia, Somalia, Sudan, Uganda and Kenya, with a focus on development and environmental control. IGADD's headquarters were later moved to Djibouti, following an agreement signed in January 1986 by the member states. Eritrea joined the organization in 1993, upon achieving independence.

In April 1995, the Assembly of Heads of State and Government met in Addis Ababa, where they agreed to strengthen cooperation through the organization. This was followed with the signing of a Letter of Instrument to Amend the IGADD Charter / Agreement on 21 March 1996. The Revitalised IGAD, a new organizational structure, was eventually launched on 25 November 1996 in Djibouti.

IGAD have partner states outside the Horn of Africa, Nile Valley and the African Great Lakes for participating at IGAD-RCP meetings on an ad hoc basis.

In September 2006, the AU Peace and Security Council approved an IGAD proposal to deploy an IGAD Peace Support Mission in Somalia (IGASOM).

On 21 February 2007, the United Nations Security Council approved Resolution 1744, which authorized the deployment of a new African Union Mission to Somalia (AMISOM) in place of IGASOM.

Ambassador Mahboub Maalim handed over as Executive Secretary to Workneh Gebeyehu in late 2019. Maalim, a Kenyan nominee, had served from 2008 to 2019.