Originally from Williamsville, Susannah attended the American Academy of Ballet for nine years. She attended summer intensives at the New York State Summer School of the Arts in Saratoga Springs, The School of American Ballet in New York City, and the Pacific Northwest Ballet School in Seattle.

She continued her training on scholarship at the School of Cleveland Ballet, where she also performed with the Cleveland Ballet. She then danced professionally for eleven years with Pittsburgh Ballet Theatre, Louisville Ballet, Milwaukee Ballet, and BalletMet in Columbus. Additionally, she taught on the faculty of the BalletMet Dance Academy.

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Over the span of her career Susannah danced numerous ballets in the classical and contemporary repertoire. Some notable roles have included Tall Girl in George Balanchine's Rubies, Queen of the Dryads in Don Quixote, Snow Queen in The Nutcracker, Summer Fairy in Cinderella, Fairy of Grace in Sleeping Beauty, and Tall Swans and Spanish Princess in Swan Lake.

After retiring from dancing, Susannah was the ballet mistress for the Festival dancers of Chautauqua Institution's School of Dance. ​She has also been a guest teacher for Ballet Western Reserve in Youngstown, Ohio, SUNY Brockport, Little Red Dancing School in Rochester, NY, and the New York State Ballet. In 2005, Ms. Dwyer was a recipient of the Business First Magazine's 40 Under 40 award.

In 2002, along with her husband founded Lockport City Ballet and two years later Classical Ballet of WNY, where they are the primary ballet teachers at the studios.​​

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