On qualification in 2003, Antonia joined city firm Kingsley Napley as a solicitor specialising in family law. In 2007 she moved to market-leading family law firm Withers LLP before founding Burgess Mee in 2013 alongside Peter.
In her time at Withers LLP Antonia acted for the wife in the reported case of JKN v JCN which involved a transatlantic divorce. More recently she was the solicitor advocate for the respondent in the High Court case of TW v PL. She has also worked on many small, medium and high net worth financial cases and complex children cases, including cases where there are allegations of sexual abuse.
Antonia has particular experience in those difficult cases where there may be one party with narcissistic traits or a personality disorder, which need to be handled with great sensitivity and care.
Antonia is recommended in the Legal 500 2018, stating she "fights her clients' corner extremely well and leaves no stone unturned" and the Legal 500 2015 “[She] ensures that the best interest of the child is always of paramount importance”. Chambers and Partners 2018 described Antonia as "a hard-working, dedicated and experienced practitioner who exudes considerable confidence and who inspires a lot of respect" and in 2016 it recommended Antonia, saying solicitors say she has “excellent strategic insight” and an “impressive intellectual prowess, matched with real humanity and compassion”.
Antonia has lectured on family law, written articles in the legal press and has contributed to text books on divorce.
She was formerly Secretary of Resolution (London Region) and sat on the steering committee for 'Parenting After Parting', an initiative designed to help separated parents rebuild their parenting relationship for the sake of the children.
Antonia co-founded the family law advice clinic at the Peckham CAB where she is a voluntary advisor and has trained McKenzie friends to assist litigants in person.