Television:
* "The O.C." (2003-2007) as "Summer Roberts": This teen drama was her breakout role and brought her widespread recognition.
* "Greek" (2007-2011) as "Rebecca Logan": Kaylee starred in this college-themed series, playing a sophisticated sorority girl.
* "CSI: Miami" (2002-2012) as "Jessie": This is one of her earliest TV roles, where she played a recurring character for a few episodes.
* "The Middle" (2009-2018) as "Jill": She had a recurring role in this sitcom, playing a character who had a complicated relationship with the main character's daughter.
* "Awkward" (2011-2016) as "Tamara": Kaylee was a guest star in this teen comedy-drama series.
* "The Last Ship" (2014-2018) as "Dr. Rachel Scott": Kaylee had a recurring role in this post-apocalyptic thriller.
* "Lucifer" (2016-2021) as "Chloe Decker": Kaylee was a series regular in this supernatural crime drama, portraying the lead female character.
Movies:
* "The Grudge 2" (2006) as "Aubrey Davis": This horror film was one of her first major film roles.
* "The House Bunny" (2008) as "Shelley": She appeared in this comedy film about a Playboy Bunny who becomes a sorority house mother.
* "A Lot Like Love" (2005) as "Young Jennifer": Kaylee played the younger version of the lead female character in this romantic comedy.
* "The Five-Year Engagement" (2012) as "Suzie": She had a supporting role in this comedy about a long-term engagement.
* "The Wedding Ringer" (2015) as "Lisa": Kaylee appeared in this comedy film about a man who hires a best man service to help him get married.
This list is not exhaustive, but it highlights some of the more prominent projects she has been involved in.