http://www.setdancingnews.net/wcss/wcsst.htm
Two hornpipes played by Tony MacMahon - Accordian, Paul McGrattan - Flute, and Kevin Glackin - Fiddle. Clip from 1987.
Quite different from step dancing is set dancing, which is the type of traditional social dancing done strictly for pleasure in rural communities in Ireland for a couple hundred years or more. 'Sets' came from quadrilles, the eighteenth and nineteenth century court dances of France which spread across Europe. Irish peasants learned the quadrilles from British landlords and soldiers and took them home to their cottages where they became the uniquely Irish sets when traditional music and steps were applied to them.

Four couples arrange themselves in a square to dance—the term 'set' refers both to the eight people in formation and to the dance itself. When the music begins they dance a variety of intricate moves and steps. One set can last from ten minutes to half an hour. The dancing is divided into separate sections called figures—when a figure is finished the music stops and the dancers remain in place waiting for it to resume. A set usually has from three to six figures, each one different but always danced in the same sequence. After the last figure the dancers thank one another and leave the floor.

Traditionally the sets weren't formally taught—children were brought to the floor at house dances by their parents or siblings and learned by repetition. Usually people knew and danced only one set, which might be different from what their neighbours danced just a few miles away. There was no need for a caller as the set was always the same and everyone knew it.

Some of the colourful set dancing terminology for the moves—round the house (dance around the set), face the hob (line up facing the front), dance at home (dance in your own position)—reflects their origin in farmhouses. Other common moves are the wheelbarrow (three facing one), little or big Christmas (four or eight spin together like a top) and ladies chain (ladies go around the opposite gent and back).

The figures of sets can be danced to several different types of music—reels, jigs, polkas, hornpipes, slides, even waltzes—and there are usually different steps for each. Reels are popular with dancers in County Clare, where experienced dancers do the sets with elaborate battering steps, beating out a rhythm on the floor with their feet as complicated as anything a drummer would do with his sticks. Down south in Cork, Kerry and surrounding counties they like all types of music in their sets, but lively polkas are most common. In other parts of Ireland the sets combine several different types of music.

While experienced dancers have the skill to perform amazing steps, dancers of all abilities can enjoy dancing sets together. The most basic step, the 'threes', is enough to get through most sets, and with practice dancers can add endless variety. There are up steps, down steps, side steps, doubles, trebles, sevens, swings, gallops, shuffles, kicks and many others, sometimes with separate variations for each type of music. Generally steps are danced in small movements close to the floor, often in a kind of gliding motion without even lifting the feet. This is why most set dancers prefer shoes with leather soles—it's harder to glide along the floor in rubber soles.