Protesters responded to a campaign on social networking websites
Hundreds of civil society activists have marched on the Lebanese parliament in an unprecedented rally in Beirut.
The protesters are calling on all Lebanese to help bring an end to the country's divisive sectarian system and replace it with a secular system.
The organisers say it is time to redefine what it means to be Lebanese.
Demonstrators blocked the main road leading to parliament, waving Lebanese flags and chanting "secularism" as security in the city was stepped up.
A leader of the march, which was organised by an independent grassroots movement, Laique Pride, addressed the crowds through a loudspeaker outside the building.
"Change must come from us," the organiser said as police set up barricades to prevent protesters from reaching the building in the capital. "Only we citizens can do this."
More than 2,000 people joined the march, news agencies reported.
Kinda Hassan, one of the organisers, told Reuters: "We cannot live in a country where they divide the chairs of the ministers according to their confessions, not their merits."
Organisers say being secular in Lebanon comes second to being a Muslim or a Christian, Shia or Sunni, Catholic or Orthodox, the BBC's Natalia Antelava in Beirut reports.
Eighteen groups make up Lebanon's multi-denominational system, and the civic rights of the members of these groups are determined by their religious leaders rather than the government.
Only religious authorities can register marriages, births or death or rule on matters of inheritance - so all Lebanese end up having different rights.
Muslims, for example, cannot adopt children; Maronite Christians cannot get divorced, and it is impossible for members of different sects to marry each other, while civil marriage is not an option here.
The government, too, is divided. Since independence in 1943, Lebanon's president has always been a Maronite Christian, its prime minister a Sunni Muslim and speaker of parliament a Shia.
Supporters of this unique system say it gives all the religious communities a voice.
But more and more young people point to its failures - chronic instability, weak central government and sectarian tension which has resulted in civil wars in the past.