When Jonathan Katz called his friend Chuck Sklar when Sklar was a roommate of H. Jon Benjamin, Benjamin's girlfriend Laura Silverman sometimes answered the phone. Jonathan was so smitten with Laura's tone of bored indifference that she became his prime candidate for Laura the Receptionist.
Contrary to the characters they played (Ben Katz and Laura the Receptionist), H. Jon Benjamin and Laura Silverman were an actual boyfriend/girlfriend team.
This was Comedy Central's first original animated series, followed by South Park (1997). The show initially ran as seven one-minute shorts on Short Attention Span Theater (1989).
First show to use the technique of "boiling lines" almost exclusively to animate what would otherwise be little better than a sequence of pictures; Tom Snyder termed this "Squigglevision". Snyder found this an easy way to turn his company's illustrators into animators for his award-winning educational software. Using it later for DKPT was a natural transition.
The creators liked Ray Romano so much that they asked him to play an office partner of Dr. Katz as a recurring character. Ray was agreeable to the idea, but soon after had to commit to Everybody Loves Raymond (1996).