After moving back to Manhattan Gastineau signed with the Elite Model Management, and became a model as part of their celebritydivision. Within weeks of signing with the agency, she appeared in a spread for Stuff magazine. She walked runways for Anne Bowen and Anna Sui during NYC fashion week in 2005, and signed an endorsement deal with L'Oréal Paris, which led to a European advertising campaign. During that time, she became the face of casual wear designer Ed Hardy. Later, Gastineau appeared on the cover of Steppin' Out, Hamptons and Lucire magazines. In 2005, she appeared on Maxim magazine's Hot 100 list, ranking at number 60. In 2006, she walked the runway for New York Fashion Week, for designer, Yumi Katsura, and the modelled for the designer's bridal collection later that year. Her successful modeling career included contracts with MAC cosmetics, as well as occasional runway shows for boutiques such as Heatherette run by Traver Rains and Richie Rich. She also shared a high-end accessory line with her mother, Tres Glam, and in 2007, they added a costume jewelry line as well. Gastineau continues to successfully pursue modelling, which includes occasional magazine layouts. She has appeared on the cover of Social Life magazine, and appearances in magazines such as L.A. Confidential and Life and Style. In 2008 at Fashion Week in NYC, she walked the runway for designer Tamara Pogosian, and was featured in a campaign for Ferrari California in Beverly Hills. She made small appearance in the movie Bruno where she was duped by the Sacha Cohen character into believing she was on a TV show when in fact, she was the victim of Cohen's role play. Currently, Gastineau makes occasional appearances as Kim Kardashians' best friend on the hit E! show, "Keeping Up With The Kardashians".
Entertainment
In 2004, Gastineau landed a development deal with the E! Network and began production on a reality series which would also feature her mother Lisa Gastineau, the ex-wife of NFL defensive end Mark Gastineau. In 2005 the series, eventually dubbed T Girls, premiered on February 15 and became a modest hit for The E! Network. The first season chronicled mother and daughter's quest for love in New York City as well as Brittny's formal, successful introduction into the world of modeling. On January 31, 2006, the series' first complete season was released on Region 1 DVD in the United States. In between seasons of The Gastineau Girls, Gastineau appeared on another E! Network reality show, , which observed the activities of spoiled celebrity children on a Colorado cattle ranch. The show was produced by Joe Simpson, father of Jessica and Ashlee Simpson. Gastineau later appeared on the NBCgame show, Identity, and guest hosted episodes of The View and Isaac Mizrahi's talk show. She appeared on Lifetime's Top This Party, E!'s Keeping Up with the Kardashians and MTV's popular programs The Hills and Cribs. She also hosted segments for Fuse TV and Spike TV. In 2009, Gastineau appeared in a small segment of the movie Brüno where she is asked to judge whether Jamie Lynn Spears should keep or "abort" her unborn baby. Gastineau said to "abort it". Gastineau said she was 'joking around' and, in a later interview, said she was aware of the satirical nature of her appearance, saying: "I was just playing along. Anyone who is going to see Bruno knows it's a comedy, and I was totally joking around! I was not serious." She says she's seen the movie and "thought it was amazing." Sacha Baron Cohen, she adds, "is a genius."
