22 Minutes received strong ratings during its earlier seasons and Walsh's character Marg Delahunty became famous for buttonholing politicians and submitting them to satirical interviews.

[6] Usually Marg Delahunty would recite a scripted piece intended to humiliate the politician, often by providing criticism and "grandmotherly" advice.

Walsh is also noted for her comical segment chronicling the Canadian Auto Workers Union's tense blockade of the Volvo Halifax Assembly plant in 1998.

On October 24, 2011, Walsh was once again in the spotlight as she reprised the role of Marg Delahunty conducting an ambush interview of Toronto Mayor Rob Ford at his home.

In 2020, Walsh reprised her longtime 22 Minutes character of Miss Eulalia in the CBC Gem web series Broad Appeal: Living with E's,[8] for which she received a Canadian Screen Award nomination for Best Lead Performance in a Web Program or Series at the 10th Canadian Screen Awards in 2022.

Besides TV acting, she has worked on movies such as Mambo Italiano,[5] Geraldine's Fortune,[14] Rain, Drizzle and Fog,[15] Buried on Sunday, The Divine Ryans, Young Triffie, Violet,[16] and The Grand Seduction.

On December 15, 2007, Walsh made national news with a story about her upcoming special, Nudity, Sexuality, Violence and Coarse Language, in which a large group of people who went and stripped naked standing next to St. John's Harbour in −11 °C (12 °F) weather to be filmed as a part of the show's closing.

"[23] She won Best Supporting Actress at the Atlantic Film Festival in 1992 for her performance in Mike Jones' Secret Nation.

[2] On November 4, 2006, Walsh and Ed MacDonald picked up a Gemini Award for the best writing in a comedy or variety program for their work in Hatching, Matching and Dispatching.

In 1993, Walsh was chosen to deliver the prestigious Graham Spry lecture which was broadcast nationally on CBC Radio.