In 1948, the church was elevated to the status of cathedral after the new Motherwell Diocese was erected as a suffragan see by the apostolic constitution Maxime interest.

The Scottish Catholic Directory of 1901 includes in the list of events for the year 1899-1900 the "Opening of the Church of Our Lady of Good Aid, Motherwell" on Monday 9 December 1900, the feast of the Immaculate Conception transferred from Sunday.

With four manuals it is the largest organ of any Roman Catholic church in the West of Scotland.

The cathedral organist is John Pitcathely, who played the organ at both of the Papal visits to Scotland.

However, these and much of the ornate decoration were lost in the re-ordering of the sanctuary in 1984 in accordance with the reforms of the Second Vatican Council.