Former Public Service Commission chairman Eddie Teo, 71, will succeed Mr J.Y. Pillay as head of the Council of Presidential Advisers (CPA) on Jan 2.
Mr Pillay, who has advised three presidents over 18 years, is retiring after his current term of appointment ends. The 84-year-old is the longest-serving CPA chairman.
In a statement yesterday, the President's Office said Mr Teo will chair the council from Jan 2 next year to June 1, 2020. He was appointed a member of the CPA on Aug 15.
Mr Teo will relinquish his post as chairman of the Presidential Council for Religious Harmony to Justice Chao Hick Tin, 76, on Jan 2.
The CPA advises the President in the use of her discretionary and custodial powers in safeguarding past reserves of the Government and Fifth Schedule Statutory Boards and government companies.
It also advises the President on the appointments of various key personnel in public service.
Mr Teo has spent nearly 50 years in public service, 10 of them as chairman of the Public Service Commission (PSC).
A President's Scholar, he began his career in 1970 in the Security and Intelligence Division of the Ministry of Defence. In nine years, he became its director at age 31, a post he held until 1994.
He was permanent secretary of defence from 1994 to 2000, and permanent secretary in the Prime Minister's Office from 1998 to 2005.
After becoming PSC chairman on Aug 1, 2008, he brought on board new members from different backgrounds and professions, from academia to social work to law.
Mr Pillay, a veteran civil servant, previously held various senior positions, including at the Finance, Defence and National Development ministries as permanent secretary, and the Monetary Authority of Singapore as managing director.
He was also chairman of Singapore Airlines from 1972 to 1996, and chairman of the Singapore Exchange from 1999 to 2010. He was awarded the Order of Nila Utama First Class in 2012 for his contributions to Singapore.
In a letter, President Halimah Yacob expressed her appreciation for Mr Pillay's "dedicated services and exceptional contributions" to the CPA over the past 18 years.
Mr Pillay was first appointed a member of the CPA in January 2001, and as chairman in September 2005.
She wrote: "As the longest serving chairman of the CPA, you provided wise counsel to three presidents - the late Mr S R Nathan, Dr Tony Tan and myself.
"We benefited from your wide-ranging experiences and deep perspectives on various issues, which helped to raise the quality of our discussions with government officials and Fifth Schedule entities...
"Your astute judgment on character, honed over years of leading in both public and private organisations, was also useful in guiding the CPA to review the nominations for key appointments in public service."