The massive sanctuary organ was built by the Aeolian-Skinner Organ Company of Boston. When first installed in 1956, the organ was 77 ranks, and contained over 4500 pipes. Further improvements were completed in 1991 and 2001, resulting in the current 81 ranks of pipes played from a four-manual console.
Acclaimed guest organists have included Marie-Claire Alain, E.Power Biggs, Pierre Cochereau, Ken Cowan, David Craighead, Catherine Crozier, Jeanne Demessieux, Maurice and Marie-Madame Durufle, John Ferguson, Virgil Fox, Robert Glasgow, Anton Heiller, Wilma Jensen, Joan Lippincott, Marilyn Mason, Karel Paukert, Russell Saunders and Alexander Schreiner.
The smaller McMillen Chapel pipe organ is a 13-rank instrument built by the Reuter Organ Company of Lawrence, Kansas.