Protesters took to the streets of Madrid and several other Spanish cities on Thursday against a government reform of the labour code that makes it cheaper and easier to fire workers.
Hundreds of demonstrators gathered near parliament in the Spanish capital as lawmakers inside debated proposed amendments to the reform, which was passed by decree in February.
Some were holding signs including "No to junk contracts" and "No to a labour reform that is unfair to workers."
The protests were organised by Spain's two main unions, the Comisiones Obreras (CCOO) and the Union General de Trabajadores (UGT), which in March staged a general strike in protest at the labour market reform.
"This reform will provoke an acceleration in the pace of the destruction of jobs in Spain," said CCOO head Ignacio Fernandez Toxo at the Madrid rally.
UGT leader Candido Mendez said unions "will not stop denouncing this law and demanding that it be changed in depth."
Prime Minister Mariano Rajoy's conservative government says the labour law reform, which reduces severance pay, is needed to attack Spain's 24.4 percent jobless rate, the highest level in the industrialised world.
But critics say the reforms unfairly favour employers and destroy hard-fought rights.
"They are making fun of us. This reform destroys all rights which workers had," said Luis Lopez Garcia, 37, who works for Madrid city hall.