A Christian British Airways (BA) employee has begun her appeal against a ruling which allowed the airline to stop her wearing a cross at work.
Nadia Eweida, 57, wants the Court of Appeal to overturn a ruling that BA did not religiously discriminate against her in 2006.
Miss Eweida, of Twickenham, south-west London, returned to work for BA after the firm changed its uniform policy.
She is claiming £120,000 in damages and lost wages.
She wants the court to overturn a November 2008 decision by the Employment Appeal Tribunal (EAT) that she was not a victim of religious discrimination.
The tribunal was told she went home in September 2006 after failing to reach a compromise with managers over the visible display of the plain silver cross on a chain around her neck.
Hijabs and bangles
The following year, the airline changed its uniform policy and Miss Eweida, a Pentecostal Christian who works in customer services at Terminal 5 at Heathrow Airport, returned to work.
But, as she was unpaid during her absence, Miss Eweida claims BA should admit its previous policy was unlawful and pay her around £120,000 in damages and lost wages.
She argues that, while Muslims and Sikhs were allowed to wear hijabs and religious kara bangles respectively, she as a Christian had been asked to remove her cross necklace or hide it from sight.
Her counsel, Karon Monaghan QC, told the Court of Appeal the EAT ruling was wrong because it concluded any discrimination must disadvantage Christians in general.
Ms Monaghan said Article 9 of the European Convention on Human Rights and the 2003 Employment Equality (Religion or Belief) Regulations respected "highly personal and individual" religious beliefs and practices.
She told the court the regulations did not require proof Christians as a whole would wish to wear a cross visibly, rather that her client was placed under a disadvantage by not being allowed to.
Miss Eweida, who is not eligible for legal aid, is being represented by lawyers instructed by human rights group Liberty at the hearing before Lord Justice Sedley, Lord Justice Carnwath and Lady Justice Smith.
The case continues.