Professional sports, as opposed to amateur sports, are sports in which athletes receive payment for their performance. Professional athleticism has come to the fore through a combination of developments. Mass media and increased leisure have brought larger audiences, so that sports organizations or teams can command large incomes. As a result, more sportspeople can afford to make athleticism their primary career, devoting the training time necessary to increase skills, physical condition, and experience to modern levels of achievement. This proficiency has also helped boost the popularity of sports.

Most sports played professionally also have amateur players far outnumbering the professionals. Professional athleticism is seen by some as a contradiction of the central ethos of sport, competition performed for its own sake and pure enjoyment, rather than as a means of earning a living. Consequently, many organisations and commentators have resisted the growth of professional athleticism, saying that it was so incredible that it has impeded the development of sport. For example, rugby union was for many years a part-time sport engaged in by amateurs, and English cricket has allegedly suffered in quality because of a "non-professional" approach.