The TCD herbarium is the only one in Ireland to contain significant holdings of non-Irish material; these are based around the huge collections of great historic importance amassed by Coulter, Harvey, Kerr and later workers.
The herbarium's holdings are large and significant by international standards (for example it holds the biggest collection of algae in Ireland and one of the biggest of any University herbarium anywhere in the world).
It is a significant resource in Irish terms - it contains an important part of the heritage of the country. Its collections and archives show, for example, the very large contribution Irishmen have made and continue to make to the exploration and study of the flora of the third world. contains reference specimens which are essential to base-line study of the Irish, European and tropical vegetation and flora.
It contains the only plant taxonomic teaching and research resource in Ireland and one of the few in Europe (plant taxonomy has, recently, been recognised as a priority research area in many European countries).
Because of its international stature the herbarium attracts students and visitors to it both from Ireland and overseas.