He then joined a research unit reporting to the Privy Council on Education and thence to the Board of Education, where he rose rapidly and served as private secretary to Sir John Gorst, Vice-President of the Committee on Education until 1902. He was responsible for some of the new ideas in the Education Act 1902, and was appointed Permanent Secretary to the Education Board in April 1903, being thus placed in a position to ensure the Board effectively implemented the act. He was appointed a Companion of the Order of the Bath (CB) in the 1902 Coronation Honours, and promoted to Knight Commander (KCB) of the order in the 1907 Birthday Honours.
In 1911 he was sharply criticized by Edmond Holmes for failings among school inspectors, in a private memorandum which then became public. He was forced to resign and then accepted a post chairing the commission to implement the National Insurance Act 1911. This included a huge and wide-ranging task of administration and even included the foundation of the precursor of the Medical Research Council. Morant promoted and largely drafted the National Insurance Act 1913, correcting problems in the previous Act.
When the Ministry of Health was created in 1919 he became its Permanent Secretary.
He died of influenza on 13 March 1920.
In 1896 he married Helen Mary Cracknell.
- Fry, Geoffrey K. "Morant, Sir Robert Laurie". Oxford Dictionary of National Biography (online ed.). Oxford University Press. doi:10.1093/ref:odnb/35096. (Subscription or UK public library membership required.)
- "William Morris: in memoriam" (PDF). The William Morris Society in the United States. Retrieved 7 November 2018.
- Davies, Alfred T. (1948). "The Greatest Civil Servant of his Day". The Lloyd George I Knew. London: Henry E. Walter. p. 77.
- "The board of Education". The Times (36916). London. 4 November 1902. p. 9.
- "The Coronation Honours". The Times (36804). London. 26 June 1902. p. 5.
- "No. 27453". The London Gazette. 11 July 1902. p. 4441.
- Rowse, A. L. (1948). "What is Wrong with the Civil Service". The End of an Epoch: Reflections on Contemporary History. London: Macmillan & Co Ltd. p. 123.