This paper explores the demand for attendance at professional sporting events using a data set that includes ticket prices and a price index reflecting prices for ancillary goods associated with attendance. Previous research has focused on attendance at Major League Baseball games, but this study also includes attendance at NBA and NFL contests. The analysis largely confirms existing findings that attendance demand is price inelastic, a result that is often thought to be at odds with the monopoly status of professional sports franchises. The analysis shows that ticket pricing in the inelastic portion of the demand curve is consistent with revenue maximization by monopoly teams that also set prices for related goods and services like concessions and parking closer to the elastic portion of the demand curve.