The Luas in Dublin is 20 years old. It was severely delayed as usual when it comes to large infrastructure projects in Ireland and it wasn't universally welcomed but now it is about to surpass 50 million journeys in a single year well in excess of its original estimates. 

So what lessons have planners learned from LUAS for other big transport projects nationwide and why can't we get stuff built on time here? 

Joining Joe this morning was Paolo Carbone, Head of Light Rail at Transport Infrastructure Ireland.