This paper explores how audiences describe and evaluate their experience of a live performance. Much of the arts marketing literature measures audience satisfaction with the entire event, including pre and post show talks, parking, ticket price, seating, merchandise and refreshments. Research undertaken at a range of live performing arts events in 2008 and 2009 revealed ‘hidden stories’ of audience members’ responses to performances. These responses are indicative of four aspects of the audience experience – knowledge, risk, authenticity and collective engagement. The stories, and their indicators, are the audience measure of quality of performance. This paper uses audience research at three contemporary theatre companies, to test and validate the audience experience as a new quality assessment instrument: the Arts Audience Experience Index.