While cross-wearing BA employee Nadia Eweida enjoyed victory at the European Court of Human Rights (ECHR), three other Christians lost their cases, including hospital nurse Shirley Chaplin, who had been prevented from wearing a cross visibly around her neck.
They will be appealing today's judgment at the ECHR's Grand Chamber.
Speaking at a news conference in central London, Ms Chaplin said she was "very disappointed" by the judgment but heartened that other Christians can now wear a cross in the workplace.
She said she still feels that other religions are given more freedom in the workplace and called upon David Cameron to live up to a promise to change the law to protect cross-wearers.
British Airways employee Nadia Eweida had argued the airline's denial of her wearing a cross contravened articles nine and 14 of the European Convention on Human Rights, which prohibit religious discrimination and allow "freedom of thought, conscience and religion".
Lawyers for the Government, which contested the claim, argued her rights were only protected in private.
But judges today ruled there had been a violation of article nine (freedom of religion), by five votes to two.
After being sent home in September 2006 for displaying the silver cross around her neck, Ms Eweida returned to work in customer services at Heathrow Airport's Terminal 5 in February 2007 after BA changed its uniform policy on visible items of jewellery.