Nicholas Roland Leybourne "Fink" Haysom (born 21 April 1952) is a South African lawyer and diplomat who focuses on democratic governance, constitutional and electoral reforms and the reconciliation and peace process.

He served as a senior lawyer with the practice and litigated high-profile human rights cases as an attorney of the High Court of South Africa during 1981 to 1993.

From 2005 to 2007, Haysom held the position of head of the Office of Constitutional Support for the United Nations Assistance Mission for Iraq (UNAMI).

From 2007 to 2012, he held the position of director for Political, Peacekeeping and Humanitarian Affairs in the Executive Office of United Nations Secretary-General Ban Ki-moon.

The United Nations Security Council expressed regret at Somalia’s decision to expel a U.N. envoy who questioned the arrest of an extremist group defector-turned-political candidate.