Seth's illustration work includes the cover artwork for Aimee Mann's album Lost in Space (2001) and the jacket and French flaps for the Penguin Classics Portable Dorothy Parker (2006).

From September 2006 to March 25, 2007, Seth serialized a graphic novel titled George Sprott (1894–1975), for the Funny Pages section of The New York Times Magazine.

In the liner notes of that publication, Seth announced he was expanding Sprott into a book, filling in gaps that were cut to meet the restraints given by NYTM.

[10] Seth's artwork has landed on the cover of The New Yorker three times, which he said was a professional milestone he was happy to achieve.

[11] Seth collaborated with children's novelist Lemony Snicket on his four-part series All the Wrong Questions, starting with Who Could That Be at This Hour?

For this exhibition one of the buildings from Seth's Dominion City project was re-built at the Kitchener-Waterloo Art Gallery as a walk-in theatre wherein visitors could sit and watch a program of black and white documentary shorts that had been produced by the National Film Board of Canada.

[1] Seth has won a number of industry awards throughout his career, and in 2011 was honoured by being the first cartoonist to win the literary Harbourfront Festival Prize.

In 2024, Seth (and "Clyde Fans") appeared in a stamp series honouring Canadian graphic novelists.