The Flagstar at Westbury Music Fair is an entertainment venue located in the hamlet of Jericho, outside of Westbury, New York. It was constructed as a theatre in the round, with seating for 2,870. It was one of many similar venues, was originally developed by Shelly Gross and Lee Guber as a means to present top performers and productions of popular theatrical musicals at a series of venues located in suburban locations on the East Coast of the United States.