Dublin Port has appointed a head of security as part of the introduction last month of an international ship and port security code.
The code, introduced by the International Maritime Organisation, is aimed at detecting and deterring threats to international security.
Dublin Port said its new security chief is Mr Guy Davies, who took up the post yesterday. He will assume responsibility for the security of the whole port estate.
As part of increased security, passengers using the three Dublin Port terminals are subject to more stringent checks in the departure area.
Car passengers are also now unable to leave the car-park and go into a terminal building without producing the necessary identification.
There are also increased levels of cars and baggage searches, while training programmes have been introduced to educate all staff to be more vigilant on security matters.
The head of operation at Dublin Port, Mr Seamus McLoughlin, said that the new arrangements would not inconvenience passengers in any way.
"We've had no negative feedback from passengers. They appreciate that it is for their own benefit."
Meanwhile, Risk Management International has been appointed by the Irish Ports Association to co-ordinate the new security operations at Dublin, Cork, Dún Laoghaire, Rosslare Europort, Waterford, Shannon Foynes and Bantry ports.