Businesses in Dublin say the Irish Rail strikes will cost the city up to €25m.
DublinTown says more than 10% of the people who travel into the capital every day use the train, and it is critical for the city's economy.
The group is urging both sides to return to the table ahead of tomorrow and Monday's work stoppages.
DublinTown CEO Richard Guiney says the disruption will have a huge impact on the city.
He said: "We estimate that the strikes could cost around €25m to the Dublin economy, so it's obviously a major concern.
"What we would say to the parties is, there is a State apparatus there for dispute resolution, and we'd like to see that being used fully."