1991–2008: Career beginningsAs a baby, Rivera appeared in commercials for Kmart, but her first significant acting job was at the age of four when she starred as Hillary Winston in the Eddie Murphy produced sitcom The Royal Family in 1991. The show received positive reviews and high ratings initially, but when star Redd Foxx suffered a sudden heart attack on set, the show never recovered and was soon canceled. Nonetheless, Rivera received a Young Artist Award nomination for her performance.
Between 1992 and 2002, she had small roles in The Fresh Prince of Bel-Air, Family Matters, Live Shot, Baywatch, Smart Guy, The Jersey, House Blend, Even Stevens and The Master of Disguise. In 2002 she also appeared in the music video for B2K's "Why I Love You". She was hired for a single episode guest appearance on The Bernie Mac Show in 2002, but she was brought back to work on a further ten episodes throughout all five seasons. She was later featured in episodes of 8 Simple Rules and CSI: Miami. In between auditions and roles, Rivera worked jobs as a telemarketer, a nanny, and a greeter at an Abercrombie & Fitch store. In 2006 and 2007, Rivera took part in a production of Mark E. Swinton's play, U Don't Know Me: The Musical, both in Los Angeles and when the production was taken on national tour.
2009–11: Breakthrough and acclaim with GleeIn 2009, Rivera was cast as Santana Lopez, a high school cheerleader, on Fox's musical comedy series, Glee, about a high school glee club. Rivera's character comes off as a cold-hearted and vicious cheerleader, who often shows her softer side to fellow cheerleader Brittany (played by Heather Morris). Rivera auditioned for the opportunity "to sing, dance and act all in the same show," and because she was a fan of co-creator Ryan Murphy's previous work on Nip/Tuck.
Rivera drew on her own high school experience of unpopularity to prepare for the role, as well as watching films such as Mean Girls to "really get in the zone and feel like a bitchy Sophomore". She has described Santana as "your typical high school cheerleader, for the most part," explaining: "She's really mean and loves boys. She's really witty so I love playing her." She has characterized Santana as "a bit of a bad girl" who is "really snarky and always has these really witty one-liners she throws out there." Rivera enjoys the fact Santana is competitive and headstrong as she herself shares those traits, but dislikes Santana's mean streak. She finds the show's pacing challenging, especially the dancing, and commented in June 2009 that her most memorable moment on Glee was performing the Cheerios' glee club audition piece, "I Say a Little Prayer". Santana played a more prominent part in the last nine episodes of Glee's first season. Rivera commented: "Santana's been wreaking havoc with people's boyfriends and people's babies and teachers—she's the high school terror, and she's going to continue to be the villain."
In January 2011, Rivera appeared in a parody of "Nuthin' but a 'G' Thang", called "Nuthin' But a Glee Thang", co-written by Glee co-star Heather Morris.
In July 2011, Rivera was nominated for two ALMA awards, in the categories of "Favorite Female Music Artist" and "Favorite TV Actress—Leading Role in a Comedy". Rivera received a great amount of critical praise for both her acting and her singing performances in the latter part of Season Two and the beginning of Season Three. As 2011 ended, she or her character was on many "Best Of" lists, including HitFix's 25 Breakout Stars of 2011, TV Guide's Best Performances of 2011, MTV's Best TV Characters of 2011, as well as others.
In the second half of the series' third season, Rivera's critical acclaim and featured role continued. She was given the opportunity to do a duet with Ricky Martin, and work with Gloria Estefan, who was cast as Santana's mother. As the season ended there was uncertainty about which characters and actors would return in the fourth season, once a large portion of the characters had graduated high school. While attending the Fox Upfronts in May 2012, Rivera confirmed that she would be returning.
2011–present: Debut studio albumIn May 2011, it was announced that Rivera had signed a deal with Columbia Records to produce a solo album. That same month, Rivera hosted the San Francisco GLAAD Media Awards. In November 2011, Rivera and Amber Riley performed at the 10th Annual Celebration of Dreams Event for the Dream Foundation. In December 2011, Rivera was revealed as the newest celebrity spokesperson for ProActiv. On March 24, 2012, she co-hosted the 23rd Annual GLAAD Media Awards in New York with co-star Cory Monteith. The two stars, along with John Stamos, continuing a tradition begun by Rivera when she hosted the 22nd Annual Media Awards in San Francisco, auctioned off kisses to the crowd, raising $15,000.
As the 2012 Emmy Awards approached, Rivera was listed by many critics and media outlets as deserving of a nomination. The Hollywood Reporter included her in their "Emmy 2012: Supporting Players" photo shoot, and Rivera was also honored by E!, Hitfix, TV Guide, and others. She was also chosen by the TV Academy to take part in a promotional video for the upcoming awards ceremony. Regarding her awards season buzz, Rivera commented to The Hollywood Reporter, "For people to even think that I'd be considered or a good candidate for a supporting actress nomination is mind blowing to me."
In October 2012. Rivera was featured in the third episode of MTV's new show, This Is How I Made It. In the episode, Rivera recounted her childhood career as an actress and a model, as well as the lean times that came between the age of 16 and 21, leading up to her big break of being cast on Glee. In December 2012, Rivera attended the annual Trevor Live event, where she performed her take on the song "Silent Night." Also in December 2012, the duo 2Cellos released the second single to their second album, a cover of Muse's "Supermassive Black Hole" featuring Rivera. She also starred in the music video for the song.
She has also starred in a recent M&M's commercial that aired during Super Bowl XLVII on February 3, 2013, as the girl that "Red" is referring to (and who is essentially trying to eat him) with a cover of Meat Loaf's I'd Do Anything For Love (But I Won't Do That).