According to an official UN Statement issued after the announcement on Tuesday, she will succeed Movses Abelian of Armenia, who now holds the position of Under-Secretary-General for General Assembly and Conference Management. 

"Chalet brings many years of experience in foreign policy and international issues and has considerable knowledge and involvement in the UN inter-governmental machinery," it said. 

Having served as Ambassador and representative to the General Assembly and its related Committees, the Security Council and to the funds and programmes, Chalet has held several senior management roles within the US Mission to the UN, most recently as Deputy Permanent Representative and Ambassador for UN Management and Reform 

Before joining the US Mission, Chalet served in Washington, D.C., as a senior legislative liaison between the State Department and the Appropriations and Budget Committees and members of Congress. 

She was previously a Constituent Service Representative for a member of Congress.