An event is described as standing room only when it is so well-attended that all of the chairs in the venue are occupied, leaving only flat spaces of pavement or flooring for other attendees to stand. Some venues issue standing-room-only (or SRO) tickets for a reduced cost since it can become very uncomfortable to stand through the course of an event. However some fans actually prefer standing-room-only tickets as the crowds that gather can be more active than people who are sitting down for much of the event.
For example, standing room only areas are very common at football matches across the globe and tickets sold as standing area tickets are sometimes the most popular, i.e. they are not sold merely when all seating tickets have been sold out. However, the periodic occurrence of tragedies related to standing room only areas at football matches such as at Hillsborough and Guatemala City have led to calls to eliminate such arrangements. In England, standing room, once a staple of most football stadiums there, has been practically eliminated at the highest level, all of the major stadiums have been refurbished as all-seaters. By contrast, standing room tickets are rare at major sports stadiums in the United States and Canada.