The M50 was originally planned to divert traffic travelling on National Primary Routes away from the city (a full bypass of Dublin).

Additional junctions along the motorway serve other suburbs of Dublin such as Ballymun, Blanchardstown, Cherrywood, Dundrum, Sandyford and Tallaght.

Most of these interchanges were subject to high levels of traffic congestion, as was the former toll plaza north of the West-Link bridge.

As part of the M50 upgrade works (see below), these at-grade crossings were removed, and in December 2008, the completely reconstructed interchange was open.

The Airport Motorway-Port Tunnel section of the route from J1-J3 has a speed limit of 80 km/h due to the closely packed junctions and heavy volume of weaving traffic.

However, it is an objective of South Dublin County Council to construct a new junction and use it to provide local access to the Cloverhill area of Palmerstown.

[citation needed] This is also very unlikely to happen as the NRA have stated they are against the provision of new interchanges on the existing M50 as they are seen to contribute to traffic congestion on the route and undermine its function as a motorway.

This plan is controversial, as it would require a tunnel across Sandymount Strand to or possibly through Booterstown marsh bird sanctuary.

A motorway reservation from Sandyford to Booterstown was included in the Dún Laoghaire–Rathdown Development Plan, with space allowed for an interchange where it crosses the N11.