Shaffer spent the bulk of her professional career with the National Film Board of Canada (NFB), directing short documentaries and dramas.
Her documentary I'll Find a Way, about a young girl with spina bifida, won the 1977 Academy Award for Best Live Action Short Film.
To a Safer Place (1987) was an uplifting story of an incest survivor in her thirties who succeeded in building a fulfilling life after years of abuse.
In June 2008, it was announced that she and colleague Paul Cowan would lose their positions as NFB staff filmmakers, due to budget cuts.
Upon graduation in 1971, she worked at WGBH-TV as a production assistant, researcher and associate producer on science and public affairs programs.