If the non-EEA national’s work starts and ends within a single 14-day period, they must request temporary permission to work in Ireland from an Immigration Control Officer at point of entry into the country. At the point of entry an immigration officer will examine the passport, and any other documents that explains the reason for the visit. Decision is then made if the non-EEA national is allowed to enter the country.
If the non-EEA national is visa required, then they must apply for a short stay business visa.
Further details on how to apply for same may be found in the section Visas above.