Lydia Annice Foy is an Irish trans woman notable for leading legal challenges regarding gender recognition in Ireland.

Having obtained the Leaving Certificate, Foy started pre-med studies at University College Dublin, but changed to dentistry a year later.

[5][6] Foy began legal proceedings in April 1997,[7] to challenge the refusal of the Registrar General to issue her with a new birth certificate.

[8] According to Foy, she had been born a "congenitally disabled woman" and the error recording her sex on her birth certificate was not only embarrassing to her but also could interfere with her constitutional rights, as she would be unable to ever choose to marry a man.

[2][9][10] Just two days after the decision against Foy, the European Court of Human Rights in Strasbourg heard a similar case (Goodwin & I v United Kingdom).

Christine Goodwin, a British transsexual, had claimed that the United Kingdom's refusal to allow her to amend her birth certificate and to marry as a female violated the European Convention on Human Rights.

According to Justice Liam McKechnie, provisions of Article 8 of the Convention protecting Foy's right to respect for private life had been violated when the State failed "to provide for 'meaningful recognition' of her female identity".

The declaration of incompatibility could not override domestic law, but did place an onus on the government to reconcile Irish and European legislation.

"[21] Initially challenging the 2007 ruling, on 21 June 2010 the Irish Government withdrew its appeal and set up an inter-departmental committee on the legal recognition of transsexuals.

On 27 February 2013 Free Legal Advice Centres, representing Lydia Foy, announced that she had issued new proceedings in the Irish High Court seeking orders requiring the government to act on the judgment of Mr Justice McKechnie in 2007 and enable her to obtain a new birth certificate recognising her female gender.