In tennis, a singles player or doubles team that wins all four Grand Slam titles in the same year is said to have achieved the Grand Slam or a Calendar Year Grand Slam. If the player or team wins all four consecutively, but not in the same calendar year, it is called a Non-Calendar Year Grand Slam. If a player wins all four at some point in his or her career, even if not consecutively, it is called a Career Grand Slam.

The four Grand Slam tournaments are the most important tennis events of the year in terms of world ranking points, tradition, prize-money awarded, and public attention. They are:

• Australian Open
• French Open
• Wimbledon
• US Open