Lysaght was educated in Dublin at Gonzaga College, at University College Dublin, and at Cambridge University. He qualified as a barrister at the King's Inns, Dublin, and then at Lincoln's Inn in London. He was one of the duo that won the first Irish Times Debate in 1960 and was elected auditor of the King's Inns Debating Society in 1961. He worked for the Irish Department of Foreign Affairs as a specialist in European Union law and was seconded for 10 years as Research Counsellor to the Law Reform Commission.
- Administration of Justice in Ireland (1975) by VTH Delany; edited by Charles Lysaght
- Brendan Bracken Allen Lane, London (1979) ISBN 0-7139-0969-2
- Edward MacLysaght, 1887-1986: A memoir (1988)
- Vanishing Kingdoms: Irish Chiefs and Their Families, AD 900-2004 (2004) (joint author)
- The Times Great Irish Lives: An Era in Obituaries (Times Books 2008-09), co-authored with Garret FitzGerald.
Lysaght also reviews books for the Sunday Independent and is an authority on the minutiae of recondite past laws and practices.
- "Irish Times Debating Competition". UCC Law Society. 2011-03-31. Retrieved 2013-02-11.
- "Tenth Report 19988" (PDF). The Law Reform Commission. April 1989. Retrieved 22 June 2015.
- https://web.archive.org/web/20100508145043/http://www.alumni.ox.ac.uk/alumni_networks/regional_networks/around_the_branches/ireland_and_the.html. Archived from the original on May 8, 2010. Retrieved August 12, 2010. Missing or empty
- https://web.archive.org/web/20110630122526/http://www.drb.ie/more_details/09-06-05/For_Ireland_and_the_Crown.aspx. Archived from the original on June 30, 2011. Retrieved August 12, 2010. Missing or empty
- "The Irish Peers and the House of Lords - The Final Chapter". Burkes Peerage. 1999. Retrieved 2013-02-11.