Designed by architect Patrick Keeley and begun in 1848, the Cathedral is an early example of neo-gothic design inspired by Augustus Pugin and the Cambridge Ecclesiology movement.  By 1852, the main body of the Church was complete except the chancel and sacristies at the west end, and the spires of the two towers above the base of the triple lancets.  The north tower was completed in 1862, the south tower in 1886, and the apse and sacristies in 1892.

In 1996, Bishop Howard Hubbard of the Roman Catholic Diocese of Albany appointed a restoration committee; headed by Father William Pape, to grapple with the numerous issues involving the roof, masonry, and interior.  MCWB was hired to prepare a phased restoration plan.  Phase I addressed the worst of the exterior building deterioration, particularly stone masonry at the north tower and clerestories, and replacement of the main upper roof.  Phase II involved the comprehensive restoration of the interior. Stabilization of the facade, replacement of the highly decorative carved masonry entrance portals, and complete reconstruction of the grand approach steps was completed in 2011.

MCWB also provided planning for the adjacent property to the south of the Cathedral for development as a Cathedral Center; containing a cloister, public gathering spaces, cathedral support functions, and new offices for the Dioceses.  MCWB is proud to have been working with the Albany Diocese for over 40 years on maintenance, repair, restoration, and planning at the Cathedral of the Immaculate Conception.