This is the most elaborate form of bagpipes. It used in Irish traditional music. Unlike the familiar Scottish bagpipes, you don't blow into the Uilleann pipes. Instead you operate a bellows with your right elbow. Air from the bellows pumps up the bag under your left elbow, which provides the air for all the pipes. There are seven separate pipes. The most important is the chanter: you play tunes on this pipe by opening and covering fingerholes. Three pipes are called drones and provide a continuous note: all three play the same note, but in three different octaves. The final three pipes, which are not present on all sets of Uilleann Pipes, are the regulators, which can be used to play chords to accompany the music. They are played by striking your wrist against metal keys, while simultaneously playing a tune with your fingers, pumping with your right elbow and squeezing with your left. Most uilleann pipers stamp their foot too, to provide a bit of rhythm.

The name 'Uilleann pipes' is popularly thought to come from the Irish word, uilleann meaning elbow, but is more likely to be a corruption of the word 'union', because of