Simon was admitted as a solicitor in 1982 and was in general practice until his call to the Bar. He now specialises in all aspects of family law with an emphasis on public and private law children cases.

Simon has experience in many areas of legal practice. He is a member of the Family Law Bar Association, Association of Lawyers for Children and the Human Rights Law Association. He contributes to legal journals and has lectured on various legal topics. Simon appeared in H v H (1989) 2 All ER CA (Evidence in Sexual Abuse Cases) and Re:D, (2001) 1 FLR 862 (Grant of Care Order: Refusal of Freeing Order). He was a member of the Bar Council's Working Party on Small Chambers 2007/8.