A traumatic cycle of bloodshed and deadlock has dogged Lebanese politics
Parliament in Lebanon has unanimously approved a proposal to lower the voting age to 18 from 21, but a constitutional amendment is needed to make the change.
It is expected to take several months and under-21s will not be able to vote parliamentary elections in June.
The measure is likely to benefit the Shia Muslim political groups Hezbollah and Amal who were pushing for a change.
The elections are expected to be hotly contested between Shia-led opposition allies and a Sunni-led pro-West bloc.
The confessional balance in multi-faith Lebanon is a very sensitive issue, so sensitive that no census has been conducted since the 1930s.
However, analysts believe the numbers of the Shia Muslim community are rising fastest, and gaining demographic strength at the expense of the once-dominant Christian community.
The BBC's Natalia Antelava in Beirut says if and when young people are finally allowed to cast their ballots in Lebanon the change could be dramatic.
Some clauses of the electoral law were amended last year, but MPs initially opposed proposals for lowering the voting age and introducing a quota for women in parliament.