Roy Stanley Emerson is an Australian former tennis player. He won 12 Grand Slam tournament singles titles and 16 Grand Slam doubles titles, for a total of 28 Grand Slam tournament titles. All of his singles Grand Slam victories and 14 of his Grand Slam doubles victories were achieved before the Open era began in 1968. He is the only male player to have completed the career Grand Slam (winning titles at all four Grand Slam events) in both singles and doubles, and the first of four male players to complete the double career Grand Slam in singles (later followed by Rod Laver, Novak Djokovic, and Rafael Nadal). His 28 major titles are the all-time record for a male player. He was ranked world No. 1 amateur in 1961 by Ned Potter, 1964 by Potter, Lance Tingay and an Ulrich Kaiser panel of 14 experts and 1965 by Tingay, Joseph McCauley, Sport za Rubezhom and an Ulrich Kaiser panel of 16 experts.
Emerson was the first male player to win 12 singles majors. He held that record for 30 years until it was passed by Pete Sampras in 2000. He also held the record of six Australian Open men's singles titles until 2019 when Novak Djokovic won his seventh title.