UK union leader Mick Lynch has called for a trade union revival to push back against the "global attack on workers' rights".
Mr Lynch, who is the General Secretary of the RMT union, delivered an address at SIPTU's Biennial Delegate Conference in Galway.
He said that the labour movement needed to be at the forefront of the fight against outsourcing, subcontracting, agency work and precarious work.
"We must get rid of the two-, three- and four-tier system that divides workers in the workplace and fight for the same terms and conditions for everyone," Mr Lynch said.
"We have people now in areas like health, education and transport who don't even know who they are working for.
"In Britain, this is leading to institutional racism with the jobs at the bottom of the tiered system almost entirely done by new migrants, who often don't understand their full rights."
"It's cynical exploitation," he added.
Around 340 delegates are gathering in Galway for SIPTU's conference.
Over the course of four days this week they are debating around 50 motions on topics including pay, the rising cost of living, housing and Palestine.
Other issues being discussed by delegates include remote working, precarious employment, climate change, healthcare, pensions and statutory redundancy entitlements.
