A cross border survey has found uncertainty amongst project managers in both North and South Ireland.
It found 60% of project managers say Brexit is a concern in Northern Ireland, compared to 39% in the south.
The majority said it will have a negative impact on their organisation- 87% in Ireland, 79% in Northern Ireland.
The survey, carried out by the Ireland Chapter of Project Management Institute (PMI) and the PMI Northern Ireland Committee.
While more than 50% of project managers in Northern Ireland believe their economy is not prepared for Brexit and its impact, only 25% said the same in the Republic.
Co-chair of the PMI Brexit Cross Border Working Group Peter Glynne said:
Brexit is all about large-scale change and our research highlights the impact of current uncertainty on organisations across the island of Ireland.
“In the Republic of Ireland, our research indicates that 39% of project managers are concerned about the uncertainty whilst in Northern Ireland the figure is higher at 61%.
"This highlights the importance of agile leadership, not only to successfully plan and manage Brexit related change, but also readiness to respond to a rapidly changing political and economic landscape."
In Ireland, project managers said the sectors that will be most impacted by Brexit would be Agri-foods (63%), Transport (26%) and Government (11%).
In the north, project managers said it would be Transport (39%), Government (26%) and Agri-foods (21%).