She is known for playing Winifred "Freddie" Brooks on the NBC sitcom A Different World. In animation, Summer was the original voice of Penny in the 1983 cartoon Inspector Gadget. Her other voice roles include Princess Kneesaa in Ewoks, Elmyra Duff in Tiny Toon Adventures and Pinky, Elmyra & the Brain, Susie Carmichael in Rugrats and All Grown Up!, Numbuh 5 and Cree Lincoln in Codename: Kids Next Door, Cleo the Poodle in Clifford the Big Red Dog, Princess Kida in the franchise of Atlantis: The Lost Empire, Valerie Gray in Danny Phantom, Blackarachnia in Transformers Animated, Rayna Cartflight in The Buzz on Maggie, Tiff Crust in My Life as a Teenager Robot, Priscilla Skunk in Sheriff Callie's Wild West, Maxine "Max" Gibson in Batman Beyond, Foxxy Love in Drawn Together, Magma in X-Men Legends, Yvonne and Gordon in Mrs. Munger's Class, Nebula in Guardians of the Galaxy and Witch Haggar in Voltron: Legendary Defender. She also voiced the character Mo in the Horrible Histories. She also voiced Kermit's Mom, Star and Pilgrim in Kermit's Swamp Years.