An open tournament is a quizbowl tournament in which anyone may play, as opposed to a normal collegiate tournament which limits its field to teams consisting of players representing the same school, in which all such players are enrolled. Nonstudents of all ages and mixed-school teams are encouraged at open tournaments. However, most open tournaments see a good deal of their field comprised of traditional school teams, since this is the best way for most people to arrange funding and transportation for quizbowl tournaments.
Open tournaments are sometimes also known as "masters tournaments."
Nearly all trash tournaments are open. Academic tournaments held in the summer are usually open, with the Chicago Open being the most competitive open event each year. Some regular-season collegiate tournaments are "de facto" open due to the competitive and financial need to fill out fields in any way possible, though a few (such as NAQT Sectionals and ICT, and all ACF tournaments) reject open teams in order to preserve the prestige of the tournament championship or gain meaningful data for nationals qualification. However, the presence of 1 or 2 non-traditional teams in a 10 to 15 team collegiate tournament will not usually cause it to be viewed as an "open," especially if those teams do not contend for the championship. In recent years, the number of "de facto open" tournaments has declined in most regions, either through explicit bans from editing teams (e.g. MAGNI, VCU Closed) or community pressure to ensure college-only fields.
Through 2008, ACF Nationals allowed a few open teams each year in order to get more packets and let people compete on one of the few high-difficulty sets available, but disallowed such teams from qualifying for the championship playoff bracket.
Some people, such as Ryan Westbrook, want all collegiate tournaments to be open in order to expand opportunities for participation, improve the competitiveness of tournament fields, and make more money for tournaments hosts. Others, such as Matt Weiner, support a clear line between collegiate and open events and resisting the "de facto open" trend, in order to preserve the link between institutional support and collegiate quizbowl, and avoid discouraging new teams by making them face "all-star" squads in normal events. In recent years, community consensus has limited the number of open tournaments during the academic year to at most 2 or 3 and clamped down on "de facto open" teams at other regular-season events.