Taxi services will be disrupted this morning as SIPTU drivers withdraw their services in protest at the effects of opening up the industry.
More than 1,300 members of the union are withdrawing their services from midnight until noon today .
Other representative bodies for taxi drivers, however, will not be withdrawing their services and have opposed the SIPTU action.
It is now a year since entry to the industry was liberalised by the Government.
Dublin Corporation said 4,224 new licences have been issued since last November.
The SIPTU drivers' action is in protest at the lack of progress in meeting their demands for tighter controls and better fares, said Mr Jerry Brennan, SIPTU's Dublin taxi drivers' branch official.
They claim that £319 million of family assets have been lost since the market opened up, and that many people stand to lose their homes as they cannot keep up with mortgage repayments.
They are calling on the Government to address the issue and provide compensation for those affected.
Mr Larry Kelly, of SIPTU's Dublin taxi drivers' branch, said the changes in the industry in the past year have been an "extreme burden" and have had a "bad financial effect on a lot of people" with a loss of earnings and a reduced quality of life.
"It is an issue that has to be addressed by the Government," he said.
A spokesman for Dublin Bus said the company would be providing its normal services this morning, with no extra services planned.
A spokesman for Dublin Corporation said the action by SIPTU is "not something we are particularly happy about but it is not within our control".
The other two drivers' representative organisations will not be withdrawing their services. Mr John Ussher, president of the Irish Taxi Drivers' Federation, said: "We are very disappointed our colleagues in SIPTU did not inform us of their action. We are not stopping."
He said his organisation has 2,000 members.
It was an "unusual situation for one organisation" to take action like this, as normally the representative bodies would take action together, said Mr Ussher.
Mr Vincent Kearns, vice-president of the Irish Taxi Drivers' Union, said the body was "totally opposed" to the SIPTU action, as "SIPTU didn't lift the phone" to tell them of their proposal.
He said his organisation represents 3,300 drivers.
The Irish Taxi Drivers' Union and the Irish Taxi Drivers' Federation, met yesterday and decided to write a letter of protest, listing the problems that their members have experienced from the industry's liberalisation. They will deliver it to the Dβil today.