St. Paul’s sanctuary organ was custom designed and hand-built in 1989 by J.W. Walker & Sons Ltd. of Suffolk, England.  When first built, St. Paul's was in the midst of a $4.2 million expansion project and nearly one-third of the organ was left incomplete due to a lack of funds.

In 2005, the church raised the necessary funds to refurbish and complete the organ. In late June 2006, the organ was disassembled and silenced. It was completed and re-dedicated on Sunday, October 8, 2006. Complete, the organ is one of the premiere English pipe organs in Southeast Michigan, featuring three manuals, 42 stops and more than 3,000 pipes.

"The Walker mechanical-action organ at St. Paul's is a treasure," says Marilyn Mason, university organist and organ department chair at the University of Michigan School of Music. Mason served as consultant to St. Paul's and Walker back in 1988 and 1989 when the organ was designed and first in-stalled. "It is a splendid instrument, crafted with variety in the various 'stops' or 'registers,' and has a beautiful tone."