In 2010, the Asian clam, Corbicula fluminea, was found for the first time in Ireland. The species is considered to be one of the most aggressive freshwater invaders causing strong economic and ecological impacts. This paper provides predictions for the spread, population density, and impacts of Corbicula fluminea in Ireland. Water chemistry datasets from the Republic of Ireland and from Northern Ireland were analysed to determine suitable waters for colonisation. Only 3 rivers and 6 lakes have pH levels considered too low (<5.6) for invasion of this species. Corbicula fluminea densities within a waterbody will depend on suitable substrate and food availability, with greater populations in canals, rivers and lakes with a higher trophic level. Boating and angling are likely to be the highest vectors of spread. Redevelopment of any canal sections will require risk assessment, to minimise spread. Corbicula is likely to cause negative economic effects by creating blockages in drinking and industrial water abstraction systems. The ecological impacts of C. fluminea are associated with their role as biofilters, and are therefore determined by their filtration rate and the overall population density in a given waterbody.