Henry Willis & Sons is a British firm of pipe organ builders founded in 1845. Although most of their installations have been in the UK, examples can be found in other countries.

The pipe organ is a musical instrument that produces sound by driving pressurised air through the organ pipes selected from a keyboard. Because each pipe produces a single pitch, the pipes are provided in sets called ranks, each of which has a common timbre, volume, and construction throughout the keyboard compass. Most organs have many ranks of pipes of differing pitch, timbre, and volume that the player can employ singly or in combination through the use of controls called stops.