Bonnie Cashin (September 28, ca. 1908– February 3, 2000) was an American designer, she is considered to be one of the pioneering designers of American sportswear. She created practical, uncomplicated clothing that catered to the independent woman of the post-war era.
Cashin was born on September 28, 1907 or 1908 in Oakland, California to Carl Cashin, a photographer and inventor, and Eunice Cashin, a dressmaker. The family lived in several towns in northern California during Cashin's early years, and in each, her mother would open a custom dress shop. In a 1973 interview, Cashin explained her interest in fashion: "My mother was a dressmaker and before I could write I could sew."
From L.A. to Broadway
Cashin's career began during high school when she joined a Los Angeles theatrical revue company, Fanchon and Marco as its designer. In 1934, she moved to New York to work for the Roxy Theater, where she created three costume changes a week for each of the theater's 24 dancers. Variety is reported to have described her as, at 19, "the youngest designer to ever hit Broadway."
In 1937, sportswear manufacturer Louis Adler offered her a job. She was hesitant to accept, stating, "The profit-conscious, business-like atmosphere of Seventh Avenue seemed very different to me from the atmosphere around the theater. I felt more at home with dancers, actors, artists, musicians, writers - people like that - than I did with most of the business men I met in the clothing industry." 
Hollywood Costume Designer
Before the U.S. entered World War II, Cashin designed uniforms for women in civilian defense. 
In 1943, Cashin returned to Hollywood and costume design. After producer William Perlburg recruited her, Cashin joined 20th Century Fox and created clothes for about sixty films including Laura (1944), Anna and the King of Siam (1946), and A Tree Grows in Brooklyn (1946).
Cashin enjoyed the work in Hollywood, explaining: "I wasn't designing for fashion, but for characteristics, which is the way I like to design clothes for daily wear. I like to design clothes for a woman who plays a particular role in life, not simply to design clothes that follow a certain trend, or that express some new silhouette."
In Hollywood, Cashin divorced Disney illustrator Robert Sterner.
Ready to Wear
Cashin was the first designer chosen for Patterns of The Times, American Designer Series, a monthly feature in The New York Times during the 1950s that made designer patterns available for home sewing.
In 1962, Cashin was hired by Miles and Lillian Cahn as Coach’s first designer. She designed for the company until 1974. Her classic designs for Coach during the early 1960s included the tote, the shoulder bag and a clutch-style purse with a removable shoulder strap. She also designed the trademark turn lock/toggle fastenings featured on most Coach products, as well as the company's popular bucket bag and the tongue bag.
Cashin lived and worked at UN Plaza upon its construction in 1966. Previously, she lived in midtown Manhattan near her mother, her company’s only other stakeholder with 1 percent, who once lived in an adjoining apartment and sewed her daughter’s samples for major manufacturers until her death in 1963.
Cashin was inducted into the Coty American Fashion Critics Hall of Fame in 1972.
In 1979, she established the Innovative Design Fund, a nonprofit organization based in New York that gave up to $10,000 to designers with original ideas in home furnishings, textiles, and fashion so they could transform their sketches into marketable products.
Towards the end of her life, Cashin granted design scholar Dr. Stephanie Lake exclusive and unrestricted access to her archive. Cashin described Lake as her "little sister. In 2016, Rizzoli published Lake's definitive monograph on the designer, Bonnie Cashin: Chic is Where You Find It.
Her use of leather, mohair and hardware was pioneering and the brass turnlocks that kept the top of her 1940s convertible down became a signature feature of all of her designs, including her Coach handbags.
Cashin was famous for her dog leash skirt: a long wool garment that could be instantly shortened by latching a small brass ring sewn at the bottom to a small brass clasp sewn into the waistline. In an interview with National Public Radio, Cashin explained the origin of the skirt. "My studio, out in the country, in Briarcliff, in the old carriage house, had steps that went up to a second floor. And I was constantly holding my skirts going up. I entertained a lot. And I'd be running up stairs with a martini in my hand. And so I thought I'd better hitch my skirt permanently."
The Bonnie Cashin Archive, the designer’s personal design archive, is privately owned in its entirety by her heir and biographer, Stephanie Lake. In 2019, as reported by WWD, Lake and her husband, Cory, have opened the archive to collaborative partnerships. Cashin’s trademark in clothing and handbags was registered by Lucia Kellar and David Baum.
- Nemy, Enid (2000-02-05). "Bonnie Cashin, Who Helped Introduce Sportswear to Americans, Is Dead at 84". The New York Times. ISSN 0362-4331. Retrieved 2016-09-15.
- Good Housekeeping. Hearst Corp. 1973-01-01.
- Carnes, Mark C. (2005-05-12). American National Biography: Supplement 2. Oxford University Press, USA. ISBN 9780195222029.
- Staff, From Times; Reports, Wire (2000-02-06). "Bonnie Cashin; Influential Fashion Designer". Los Angeles Times. ISSN 0458-3035. Retrieved 2016-09-15.
- Women designers in the USA, 1900-2000 : diversity and difference : Jacqueline M. Atkins [and others]. Kirkham, Pat., Bard Graduate Center for Studies in the Decorative Arts. New Haven, CT: Yale University Press. 2000. ISBN 9780300087345. OCLC 45486311.CS1 maint: others (link)
- Alford, Holly Price; Stegemeyer, Anne (2014-09-25). Who's Who in Fashion. Bloomsbury Publishing USA. ISBN 9781609019693.
- Petkanas, Christopher (2016-05-10). "The Forgotten Designer Behind Some of Fashion's Biggest Trends". The New York Times. ISSN 0362-4331. Retrieved 2016-09-15.
- "bonnie cashin, the most copied fashion designer you've never heard of | read | i-D". Retrieved 2016-09-15.
- Adams, Rachel (2017-02-11). "Miles Cahn, Co-Founder of Coach Handbags, Dies at 95". The New York Times. Retrieved 2017-02-26.
- Feitelberg, Rosemary (2016-04-14). "Bonnie Cashin as Revealed by Author and Archivist Stephanie Lake". Retrieved 2016-09-15.
- "Brooklyn Museum". www.brooklynmuseum.org. Retrieved 2018-03-17.
- Bonnie Cashin's personal archive, owned by design scholar Stephanie Lake: bonniecashin.org
- Bonnie Cashin at FMD
- Bonnie Cashin designs, circa 1933 - circa 1960, held by the Billy Rose Theatre Division, New York Public Library for the Performing Arts
- Bonnie Cashin Collection of Fashion, Theater and Film Costume Design, 1913-2000, held by UCLA Library Special Collections
- American Ingenuity: Sportswear 1930s-1970s, an exhibition catalog from The Metropolitan Museum of Art Libraries (fully available online as PDF), which contains material on Bonnie Cashin (see index)
- The definitive Bonnie Cashin monograph, Bonnie Cashin: Chic is Where You Find It” (Rizzoli, 2016)