Cornelscourt is a small suburban area of South Dublin, situated between Cabinteely and Foxrock. It has a mostly commercial rather than residential character and is best known for being the site of Ireland's first Big-box store, Dunnes Stores.

Cornelscourt consists of the houses and shops on either side of a section of the bypassed Old Bray Road between the junction with the N11 to the East. Along this strip are: a petrol station, a pub called 'The Magic Carpet' (which contained one of Ireland's first non-smoking lounges in a pub - the "Samuel Beckett" lounge, named after a former customer), a drama studio called 'Arclight', an Indian Restaurant, several take-away food outlets, a convenience store and the above-mentioned Dunnes Stores. The surrounding residential housing is laid out in suburban housing estates.

The first (and one of only two, the other being in Baggot Street) experimental drive-through bank in Ireland opened in Cornelscourt in 1990 and closed 12 years later.

The area has been designated a 'District Centre' by Dun Laoghaire County Council. A local area plan for the area is currently being implemented with the aim of making aesthetic and functional improvements through redesign of road layout, street furniture etc