Each person in the room had to state aloud which comparison line (A, B or C) was most like the target line. The answer was always obvious. The real participant sat at the end of the row and gave his or her answer last.

There were 18 trials in total, and the confederates gave the wrong answer on 12 trails (called the critical trials). Asch was interested to see if the real participant would conform to the majority view.

Asch's experiment also had a control condition where there were no confederates, only a "real participant."