The connection of the rail network and the development of commercial, industrial and dockside activities on the southern banks of the river further contributed to South Brisbane's growth.

[1] The expansion of the population meant that the chapel was no longer adequate to the needs of the South Brisbane congregation and a meeting was held in August 1889 to discuss the construction of a new and larger church.

Much of their work together was for the Roman Catholic Church and included important commissions such as Dara, Archbishop Dunne's residence at Petrie Bight, St Stephen's Girls' School in Charlotte Street and a convent for the Sisters of Mercy in Warwick, Our Lady of Assumption Convent, now a private building called the Cloisters.

The concrete rendering was postponed and several parts of the building including the eastern end and the rose window were temporarily constructed from timber.

A substantial bell housed in a timber belfry was erected in 1914 adjacent to the church and in 1915 a convent for the Sisters of Mercy was constructed, diagonally opposite the school on the corner of Cordelia and Peel streets.

The interior of the chancel with its marble wall linings and altar rails, terrazzo floors, domed plaster ceiling and stained glass windows was more ornate than the rest of the church.

[1] With the influx of Catholic immigrants into the area after World War II, St Mary's became an important gathering place for a number of ethnic groups.

Italian, Dutch, Polish, Lithuanian and Slovenian people attended St Mary's for services conducted by their own priests.

Many of his parishioners left the church with him to continue holding services as St Mary's Community in Exile at the Trades and Labour Council building on Peel Street (200 metres (660 ft) away).

An imposing rendered masonry building with corrugated iron roofs the church is located on the highest part of the site near the western corner.

In the eastern part of the site facing onto Merivale Street is the former presbytery, a timber building on stumps with corrugated iron hip roofs.

The nave, a double height space with a clerestory, projects forward of the single storey side aisles to form the main facade or liturgical west front of the church.

The chancel, sacristy and vestry, all additions at the rear of the church, have smaller separate roofs that are largely concealed by parapet walls.

The arrangement and form of the church is based on the traditional model of the basilica, originally a type of Roman public building that early Christians adapted for worship.

A two-storey structure, taller than it is wide, the symmetrical west front is divided into three bays and surmounted by a parapeted gable in the form of a broken bed pediment.

The central bay of the facade contains the main entrance to the church, an imposing arched opening with a shafted jamb framing a recessed doorway.

A small square window centred in the base of each bay has unusual moulded surrounds including jambs terminated by a stylised volute and a coved cornice with a leaf pattern.

Other facade details include rosettes, dogtooth banding, acanthus leaf capitals to pilasters and arabesque ornamentation on the pediment.

The main decorative detail on the side elevations is a double-layered arched corbel table running along the top of the aisle walls between the engaged piers.

[1] The chancel, sacristy and vestry, additions to the rear of church were built using similar materials and details to the original part of the building.

The interior of the church, well lit by natural daylight, has rendered white painted walls, dark stained timber ceilings and choir mezzanine and a concrete floor.

Quarter-turn timber stairs with winders in the northern corner of the west front lead up to the stepped choir platform, a balcony-like space housing the organ and overlooking the nave.

[1] A colonnade of four round arches supported by stumpy columns on tall pedestals runs along the north and south edges of the nave separating it from the aisles.

It has a mosaic tiled and marble floor, quatrefoil stained glass windows over pilasters surmounted by arches in low relief.

Surviving evidence of South Brisbane's former character as a predominantly working class suburb, the church reflects the Irish and proletariat origins of the congregation.

Built without the proposed belltower and transepts and not completed at its opening, the church also shows the impact of economic hardships experienced in the 1890s.

Modelled on the basilica, St Mary's was designed in an eclectic manner typical of late 19th century architecture but in a style that was then unusual for churches in Queensland.

In particular St Mary's has a special association with the migrant Catholic communities that developed in South Brisbane after the Second World War.

[1] In 2011, a feature documentary has been made about Kennedy and the exiled community and their conflict with the Catholic Church, entitled The Trouble with St Mary's.

[4][5] In 2016, the play St Mary's in Exile was written by David Burton about the events that led to the removal of Father Peter Kennedy as parish priest.