"Loyalty" (stylized as "LOYALTY.") is a song by American rapper Kendrick Lamar featuring Barbadian singer Rihanna from the former's fourth studio album Damn, released on April 14, 2017. The song was later sent to urban and rhythmic radio June 20, 2017, as the second single from the album. The sixth track on the album (ninth on the Collector's Edition of Damn), the song was written by the artists alongside producers DJ Dahi, Sounwave, Terrace Martin, and Anthony "Top Dawg" Tiffith. The song won the Grammy Award for Best Rap/Sung Performance.
The song contains a reverse sample of "24K Magic" produced by Shampoo Press & Curl and The Stereotypes, and performed by American singer Bruno Mars. The song also contains a "replay" of Jay-Z's "Get Your Mind Right Mami" from his fifth album ' (2000), which can be heard at its 40-second mark.
Complex calls it a "standout track" and one of Damns most "radio-friendly cuts". The Fader writer Jason Parham calls "Loyalty", "anxious, berserk, and beautifully intransigent in [its] own right" and "equal parts pop, funk, and brooding rap hymnal". Frank Guan of Vulture enjoyed the song, especially Rihanna's part, saying "though only eight bars, Rihanna's sung rap is as fluent as it is brief, a swift and casual tour of her accomplishments." Rap-Up called the song a "standout track that allows Kung Fu Kenny and Bad Gal RiRi to address allegiance from a variety of angles".
The music video for the song was released to Lamar's Vevo channel on YouTube on July 28, 2017. It was directed by Dave Meyers and The Little Homies and includes an appearance from featured artist Rihanna. Jordan Darville of The Fader gave the music video a positive review, praising the visuals and called Lamar and Rihanna's adventure together "carefully crafted [and] suitably amorous."