With the approval of the estate of Rex Stout, journalist Robert Goldsborough wrote several Nero Wolfe mysteries. Goldsborough's approach was faithful to the Rex Stout works, but he added his own touches, including an updated frame of reference (Archie now uses a personal computer to file Wolfe's germination records; Wolfe's ancient elevator is finally replaced by a more efficient model, etc.).
In 2012 Mr. Goldsborough published Archie Meets Nero Wolfe: A Prequel to Rex Stout's Nero Wolfe Mysteries. (Click the link to order through Amazon.)
On January 28, 2014, a new Nero Wolfe mystery will be published: Murder in the Ball Park