The R&A (or more formally, the R&A Trust Company (No. 1) Limited) is the collective name of a group of companies that together play a significant role within the game of golf. Historically, "the R&A" was a colloquial name for the Royal and Ancient Golf Club of St Andrews; in 2004, the club spun off its previous governance and tournament organisation roles into the current R&A group, with the club itself reverting to a private members-only club. The R&A is based in St Andrews in Scotland. The R&A is the sole owner of three subsidiary companies: R&A Rules Limited, R&A Championships Limited, and R&A Group Services Limited.

R&A Rules Limited is one of the governing bodies of golf worldwide, alongside the United States Golf Association (USGA). The USGA governs in the United States and Mexico, and the R&A in the rest of the world. They both share a single code for the Rules of Golf, Rules of Amateur Status, Equipment Standards and World Amateur Golf Rankings.

R&A Championships Limited organises The Open Championship, which is the world's oldest international men's major golf championship; the Women's British Open; the Senior Open Championship; plus the Walker Cup and Curtis Cup.

The Royal and Ancient Golf Club founded what is now the Official World Golf Ranking for male professionals in 1986, and the R&A introduced the World Amateur Golf Ranking for male amateurs in 2007. The R&A also owns and operates The R&A World Golf Museum.