Eric Trump, the 33-year-old son of US President Donald Trump, has arrived at the Trump International golf resort in Doonbeg Co Clare for a series of business meetings at the course.
Mr Trump arrived by helicopter from the Trump International links course in Aberdeenshire in Scotland to the resort.
The group, which owns over 40 golf courses in the US and Europe, bought Doonbeg for an estimated €8m in 2014.
It has since spent several million euro developing the greens and fairways at Doonbeg.
Some of the greens have been badly damaged by coastal erosion along the sand dunes and a plan to build a wall of rock armour along Doughmore beach adjacent to the course has now been abandoned because of planning difficulties.
A new plan to build scaled down defences has been lodged and a planning decision is not now expected until August.
Mr Trump will have a series of meetings with management and staff at Doonbeg tonight and all day tomorrow before returning to the US on Thursday morning.
A number of gardaí are on duty at the Trump resort at Doonbeg and are carrying out security checks of personnel and vehicles entering the golf course.