There have been major problems caused for some sports by either the increase of professionalism, or attempts to resist the spread of professionalism.
Professionalism has another influence through organisations seeing it as an attack on the central ethos of sport, i.e. the ethos of being done for its own sake and for pure enjoyment, rather than as a means to earning a living. Consequently, there has been some reactive resistance to professionalism in some organisations, and some people see this as having impeded the development of the sport. For example, Rugby football was seen for many years as a part-time sport engaged in by amateurs, and English cricket is alleged to have suffered in quality because of a non-professional approach.
See also list of professional sports leagues.