The S.League, officially known as the Singapore Premier League, is the top professional football league in Singapore. Established in 1997, it features clubs from across the country competing for the championship title. The league operates on a system of promotion and relegation with the lower divisions, enhancing the competitive nature of the sport. The S.League typically runs from February to October each year, with teams playing each other in a round-robin format. The league has seen various clubs, including Lion City Sailors and Albirex Niigata (Singapore), contributing to the growth of football in the region.