Roger Jason Stone (born Roger Joseph Stone Jr.; August 27, 1952) is an American right-wing political activist, consultant and lobbyist. He is a prominent consultant and lobbyist within the New Right, and Donald Trump's longest-serving political adviser. He was the subject of widespread media coverage for the Mueller special counsel investigation and his alleged involvement with and connections to Russian interference in the 2016 U.S. presidential election as a consultant for the Trump campaign.

Since the 1970s, Stone has worked on Republican campaigns, including those of Richard Nixon, Ronald Reagan, Jack Kemp, Bob Dole, George W. Bush, and Trump. He co-founded a lobbying firm with Paul Manafort and Charles R. Black Jr. The firm became Black, Manafort, Stone and Kelly (BMSK) in 1984. BMSK became a top lobbying firm, leveraging White House connections for high-paying clients, including U.S. corporations, trade associations, and foreign governments. Stone's style has been described as "a renowned infighter", "a seasoned practitioner of hard-edged politics", "a Republican strategist", and "a political fixer". Stone has called himself "an agent provocateur". He has described his political modus operandi as "attack, attack, attack—never defend" and "admit nothing, deny everything, and launch a counterattack", all evocative of associate Roy Cohn.

Stone first suggested Trump run for president in 1998 while lobbying for his casino business. He left the Trump campaign on August 8, 2015. In 2018, two associates alleged Stone claimed contact with Julian Assange during the 2016 campaign. Assange denied meeting Stone, and Stone said any mention was a joke. Court documents in 2020 showed Stone and Assange exchanged messages in June 2017. Unsealed warrants in April 2020 revealed Stone's 2017 contacts with Assange and that Stone orchestrated hundreds of fake Facebook accounts and bloggers for a political influence scheme.

On January 25, 2019, Stone was arrested at his Fort Lauderdale, Florida, home in connection with Robert Mueller's investigation and charged with witness tampering, obstructing an official proceeding, and making false statements. In November 2019, a jury convicted him on all seven felony counts. He was sentenced to 40 months in prison. On July 10, 2020, days before Stone was to report to prison, Trump commuted his sentence. On August 17, 2020, Stone dropped his appeal. Trump pardoned Stone on December 23, 2020.

Since 2023, Stone has hosted a show on WABC radio eponymously called "The Roger Stone Show".Roger Stone, licensed under CC-BY-SA, full list of contributors on Wikipedia.