The original design was the brainchild of designer Angela Murphy who achieved a lovely cozy atmosphere with an Italian accent. Seating is for approximately for 50 people. The next thing to consider was the staff. The original chef is son of the owner of the well known"Quo Vadis" restaurant and with his help the original menu was conceived. Declan wanted to produce good, fresh, reasonably priced food with a distinctly Italian flavour coupled with good reasonably priced Italian and new world wines. The menu has been revamped on a number of occasions but in essence has changed little from the original. In the beginning the staff consisted of 6 people, they now employ 20.
In 1996 Declan with his brother Stephen decided it was time to replicate the success of Ranelagh and set about finding a similar location. They found what they wanted in Terenure. Mario's Terenure is once again located in a village, central location with a pub across the road. It opened in april 1997. It is totally different from Ranelagh being larger and more modern, yet it achieves the same cozy atmosphere. Once again the design was conceived by Sinead Moore. Seating accommodation is for 60 people. It started with key staff from Ranelagh and went from there.
In 1999 Stephen and Declan once again went Looking for a location for a restaurant and found another site in a village with a really central location and pub the next door. This time, however they started from scratch. They bought the premises, demolishing the original building and came up with a gem. The architects were Mahony Architecture and the design, down to cups and saucers came from Sinead Moore. This time the Wine Bar was incorporated in the restaurant. Mario's Sandymount opened in August 2000. Key original staff come from Terenure and Ranelagh. The number of staff for first week was 18, they now employ 35. The menu and wines once again are the same as both other restaurants. Mario's Restaurant in Sandymount has proved extremely popular in an area that badly needed a quality restaurant.