Larry (William Sanderson), Darryl (Tony Papenfuss) and Darryl (John Voldstad) were supposed to be one-time characters, but the studio audience's reaction to their introduction was so spontaneous the producers decided to make them regular characters..
It was Bob Newhart's idea to begin using film from season two onward in order to give the show a more realistic look.
The opening credits are outtakes of On Golden Pond (1981). If you look closely, you can see Henry Fonda and Katharine Hepburn in the car. William Lanteau, who was the recurring role of Chester in the series, was also in On Golden Pond (1981).
Exterior scenes of the Stratford Inn were those of the Waybury Inn in Vermont.
Mary Frann (Joanna Loudon) visited several Vermont inns to do research and brought back the Pfaltzgraff dishes that are seen as props in the Stratford Inn.