The Harvard Din & Tonics (or "the Dins") are a signature, five-part jazz a cappella group from Harvard University, founded in 1979.
 The group was founded in April 1979 as a public service project of the Phillips Brooks House Association at Harvard College in Cambridge, Massachusetts, performing for the university community and local charitable organizations.  Their repertoire was derived in part from the Dunster Dunces, an earlier Harvard a cappella group that was active from 1946 until 1968. Their first public concert was at Yale University in November 1979, amidst the pageantry of the Harvard-Yale football game.
 The group performed in their first film in 1982, entitled First Affair and starring Melissa Sue Anderson and Loretta Swit. They also appeared in the movie Mona Lisa Smile, a 2003 film starring Julia Roberts that was set at Wellesley College.
 The Harvard Din & Tonics celebrated their fortieth anniversary with a concert at Harvard's Sanders Theater on April 13, 2019.
 Previously an all-male ensemble, the group admitted its first woman member in 2018, and a second in 2019.
 The name Din & Tonics is a pun on the popular drink the gin and tonic, and the words din, meaning a loud noise, and tonic, a musical term meaning the first note of a musical scale.  The lime green socks worn by the group's members are said to represent the lime that is traditionally served with the gin and tonic, hence the group's slogan, "A cappella with a twist."
 The Dins, composed of 12 to 15 undergraduate students, is an entirely self-directed group.  Most of their arrangements are written by current or former members of the group.  Their repertoire consists primarily of jazz standards from the Great American Songbook, as well as humor songs drawn from various periods and styles. Their repertoire also extends at times to numerous other genres, including folk, rock, calypso, spiritual, and pop.  They regularly perform in white tie, tails, and their signature lime green socks.
 The Din and Tonics began performing their own arrangement of "Sh-Boom" (generally regarded as the first popular doo-wop song after it became a #1 hit on the Billboard charts in 1954) in 1979. It has served as the Dins' signature song, and they have performed it at almost every concert since. "Sh-Boom" is featured on fourteen of the group's fifteen albums.
 The Dins have appeared on television shows, including The Price Is Right and Good Morning America, and have performed the "Star Spangled Banner" for the San Francisco Giants, the Tampa Bay Lightning, the Los Angeles Lakers, the PGA's Ryder Cup, the Boston Red Sox and the New York Yankees, the Boston Celtics, the Boston Bruins, and the Boston Breakers.
 The Dins have performed overseas since the founding of the group, and began touring Asia regularly in the late 1980s.  Since 1990, the Dins have gone on world tours biennially.  Each tour is between 2 and 3 months long and includes performances in roughly 15 countries in Europe, Africa, Asia, Australia and North America.  Additionally, they travel regularly to Vail, Colorado, Washington, D.C., New York City and spend spring break performing in Bermuda or Whistler, BC.
 The Dins have toured in: Australia, Austria, Belgium, Canada, China, Cyprus, the Czech Republic, Denmark, Egypt, Fiji, France, Germany, Greece, Hong Kong, Iceland, India, Indonesia, Ireland, Italy, Japan, Luxembourg, Malaysia, Mexico, Morocco, Nepal, Serbia, Singapore, Slovenia, South Korea, Sweden, Switzerland, Thailand, the United Kingdom, and the Vatican City.
 While on tour in 2010, the Dins performed at the closing ceremonies for the Shanghai Expo music festival.
 In January 2017, the Dins performed the National Anthem for the Los Angeles Lakers at the Staples Center in Los Angeles, following a performance with the Harvard Krokodiloes for the Harvard Club of Southern California.
 The Dins have performed for jazz vocalists Ella Fitzgerald and Bobby McFerrin, for members of the New York Voices, singer Lionel Richie, jazz pianist Herbie Hancock, jazz trumpeter Wynton Marsalis, former governor and professional wrestler Jesse Ventura, actresses Julia Roberts, Kristin Chenoweth, Sharon Stone, Jessica Lange, Kathie Lee Gifford, and Kathleen Turner, television host Conan O'Brien, actor Andy Garcia, comedian Jackie Mason, Maestro Keith Lockhart of the Boston Pops, cellist Yo-Yo Ma, Caroline Kennedy, former U.S. President Bill Clinton, as well as the Governor of Bermuda and the U.S. ambassadors to Australia, Germany, Greece, Nepal, Ireland, Morocco, Norway, Italy and Belgium.
 During their world tour, the Dins have recently performed with the award-winning German vocal quintet Vocaldente and Icelandic vocalist Andrea Gylfadóttir.[citation needed]
 More recently, the Dins performed for John Williams and the assembled graduates at Harvard's 366th Commencement, to celebrate his distinguished career. The group performed an original medley of his most notable songs, ranging from Jaws to Star Wars and Indiana Jones.[citation needed]
 They have appeared in the films "Mona Lisa Smile" and "First Affair.[citation needed]
 The Din and Tonics have produced 18 albums thus far: