Commuters are facing an unending cycle of transport chaos, with further strikes on the horizon.
Some 155,000 people will be hit by the first of five 24-hour stoppages at Irish Rail today.
More claims for pay rises, likely to cause further disruption, will be in the pipeline soon after rail passengers suffer the consequences of the latest wage demand in the run-up to Christmas.
Unions are set to lodge a fresh pay claim at Dublin Bus, as the final increase in a three-year deal is paid in January.
That demand will come around the same time as a pay review is due at Bus Eireann, which was agreed following three weeks of strikes last April.
Passengers have endured crippling strikes at all of the CIE companies since Luas drivers won a 3.75pc-a-year increase last year, and other transport staff demanded the same.
Today's rail strike will affect 70,000 Dart users, 45,000 users of commuter services, and 40,000 InterCity customers.
More strikes have been planned for November 14, November 23 and December 8.
Transport union leader Dermot O'Leary said unions will put in a new pay demand at Dublin Bus next summer.
A three-year agreement was reached at Dublin Bus last year after six days of strikes.
But the deal, put forward by the Workplace Relations Commission last September, was backdated, which means it only stretches to January.
"There will be an unending cycle of strikes unless each of the three companies come forward separately and give us what we want, and that's not going to happen," said Mr O'Leary.
"Until such time as the National Transport Authority, the department, unions and company sit around the table and factor in how they are going to deal with pay, we're going to have these disputes on a cyclical basis," he added.
"Disputes at the three companies could collide."
He said it was unsustainable that the CIE contracts restrict the level of profits that can be made and left no room to address pay.
"The NBRU [National Bus and Rail Union] is of the view that there is a requirement for all parties to come together and create an environment to periodically - perhaps in advance of the contract being awarded - discuss pay," said Mr O'Leary'
"Such a scenario would obviate the necessity to regularly engage in disruptive industrial action across the various modes of transport."
The Irish Rail strikes will cost the company €900,000 a day, while workers will lose earnings, although they will get strike pay.
Unite regional officer Willie Quigley warned that the dispute could escalate without "meaningful engagement by management".
However, some sources predict that the industrial action may be halted ahead of the third strike day, which is due to take place when Ireland take on Denmark in a World Cup play-off at Lansdowne Road.
They believe that the Labour Court will issue an invitation to talks before the dispute reaches that stage. If staff get the rise they want, the average wage at Irish Rail would rise by more than €6,000 to almost €61,000 a year.
Their pay rises in yearly increments until they reach the top of the scale.
The Transport Salaried Staffs Association said a "strong, coordinated response" is required to get an improved pay offer from the company after nine years with no pay rises, a greater workload and cost cutting.
"If we are to send a strong message that we are serious about getting a just and fair settlement, then it is now through standing shoulder to shoulder with your colleagues on the picket lines," said a message to members.
It said talks to end the row had been heading towards finalising a document to be put to members when the proposed deal was "pulled at the behest of your CEO", David Franks.
Irish Rail is automatically cancelling bookings seven days before the date of travel.
Those with monthly and annual tickets can also apply for refunds.
The commercial semi-state company said it is dangerously close to insolvency and its precarious finances will be weakened further by the industrial action.