In 1994, he wrote three episodes for the ABC teen drama My So-Called Life. He created Relativity in 1996 but the TV series was cancelled after 17 episodes. He subsequently created Roswell who gained cult following.
Katims worked on the NBC series Friday Night Lights as head Writer and executive Producer. He was nominated for a Writers Guild of America Award for Best New Series at the February 2007 ceremony for his work on the first season of Friday Night Lights. He was nominated for the WGA Award for Best Dramatic Series the following year at the February 2008 ceremony for his work on the second season of Friday Night Lights. Katims was nominated for Best Dramatic Series a second time at the February 2009 ceremony for his work on the third season of Friday Night Lights. He was nominated for the WGA Award for Best Drama Series for the third consecutive year at the February 2010 ceremony for his work on the fourth season. In 2011, he was honored by an award for Outstanding Writing for a Drama Series in Friday Night Lights.
Katims is also the creator of and executive Producer for another NBC series, Parenthood, based on the feature film of the same name and a short-lived TV series that followed; Katims' series debuted in 2010 and ended in 2015. Katims based that series' Max Braverman character on his life with his own son, who has Asperger syndrome.
Katims developed About a Boy, a 2014 TV series based on the novel of the same name, for NBC.
