Having started his career making rafting videos on the Tully River in Queensland, Australia, Einhorn is best known for his work on The Office. He also directed The Accountants, a ten-part webisode spin-off of The Office which appeared online between the second and third seasons. Einhorn has directed episodes of Survivor, for which he was nominated for two Emmy Awards.
He also directed many episodes in season 5, 6 and 7 of lieutenant"s Always Sunny in Philadelphia, and all but three episodes of Wilfred.
In May 2015, it was announced that Einhorn would be executive producer and director of The Muppets, executive produced and co-created by Bill Prady (co-creator, The Big Bang Theory) and Bob Kushell (Anger Management, 3rd Rock from the Sun, The Simpsons).