Turkish state universities have the right to ban Muslim headscarves, the European Court of Human Rights in Strasbourg has ruled.
Headscarves have been banned in some European schools
It rejected an appeal by a Turkish student who said the ban - and her subsequent exclusion from class - violated her freedom of religion.
Turkey's government had argued that headscarves violated the secular nature of the state.
Correspondents say the decision could have implications for other countries.
France barred the wearing of conspicuous religious symbols in its state schools earlier this year.
The case was brought by a medical student, Leyla Sahin, who was blocked from sitting exams at Istanbul University in 1998 and later refused permission to enrol in the faculty.
She argued that the ban was discriminatory, and violated her human rights and her right to an education.
In its ruling, the court said that measures taken in universities "to prevent certain fundamentalist religious movements from pressuring students who do not practise the religion in question or those belonging to another religion" could be justified under the European Convention on Human Rights.
Bans issued in the name of the separation of church and state could therefore be considered "necessary in a democratic
society", it added.
A second Turkish woman, Zeynep Tekin, brought a similar case before the court but withdrew her complaint in February last year.