A multiple Emmy Award-winning writer—director, he began his diverse career as a fiction writer, performance artist and video artist. In the 70s he performed at Franklin Furnace, the Kitchen, La Mamelle, Dance Theater Workshop and other performance venues. His specialty was performing in the dark under the performance persona Marshall Klugman and his last performance in the early eighties at DTW was entitled an "Evening of Stories and Tricks You Won't See Anywhere." His video narratives were shown at MOMA, Anthology Film Archives, the Kitchen and similar venues as well as broadcast on WNET and Alive From Off Center. He received numerous grants from CAPS, NYSCA, NEA, AFI and others for his video and performance work.

Kriegman was also known for being an early audio artist creating "The Telephone Stories" which were a series of radio plays for the telephone that were a very early instant on dial in art. In addition to being available on a special phone line, "The Telephone Stories" toured museums and galleries around the country after premiering at the Whitney Museum and later the High Museum and The Boston Institute of Contemporary Art.

As a short story writer, his work has been published in The New Yorker, Between C&D, the National Lampoon, Army Man, Glamour and Harper’s Bazaar. In the 1980s, he joined the team of Saturday Night Live as a performer, writer and filmmaker where he made three films including one with then clown Bill Irwin. He was also a contributor to Saturday Night Live writer—performer Michael O'Donohue's Mr Mike's Mondo Video. Soon after, Kriegman began creating, developing and producing series for Comedy Channel, Nick at Nite, Disney Channel and Nickelodeon.

At Comedy Channel he produced The Sweet Life with Rachel Sweet, and Higgins Boys and Gruber.

At Nickelodeon he created Clarissa Explains It All, and developed Rugrats, Ren and Stimpy, Doug, and Rocko's Modern Life. He was the Nickelodeon Executive Story Editor on those series. Clarissa Explains It All was notable for identifying the preteen genre and being the first sitcom for kids with a female lead that was watched equally by both genders. It featured a unique style of talking to the camera, paintbox graphics and animation and fantasies.

At Disney Channel he created Bear in the Big Blue House and Book of Pooh, and developed Life with Derek with Shaftsbury Films.

At PBS Kids he created the series It's a Big Big World, which is currently airing on PBS and around the world.

As a screenwriter he has written for Universal, Disney and Columbia Pictures. He also wrote the story and co-wrote the screenplay Elmo in Grouchland with Joey Mazzarino the screenplay for the Sesame Street movie The Adventures of Elmo in Grouchland, a co-production with Sesame Workshop and The Jim Henson Company and Columbia Pictures, as well as the script for the Bear in the Big Blue House stage show.

He has won four Emmy Awards and is the winner of the DGA award and has been nominated for a WGA Award. Bear in the Big Blue House garnered him two Emmys for Best Direction (in 2000 and 2002), as well as the Directors Guild Award in 1998 and 2000. His work on The Book of Pooh was recognized with a Best Direction Emmy in 2001. Other awards include an Emmy for Rugrats, three Parents Choice awards for Clarissa Explains It All and one for Clarissa and Peter and the Wolf, and the UNIMA-USA Citation of Excellence for “Bear in the Big Blue House,” and for Book of Pooh, as well as numerous others.

He was the co-owner of East Hampton Studios and Wainscott Studios in the Hamptons, New York, where "It's a Big Big World" is produced until 2009.