Dorothy is Elmo's pet goldfish who first appeared on the "Elmo's World" segment of Sesame Street. At six years old (in goldfish years), she is a good friend to Elmo, who can understand what she's saying through her goldfish bowl. Dorothy is inquisitive and possesses an active imagination. Whatever topic is explored, Dorothy mentally pictures a version of Elmo in an appropriate role or form.
Dorothy is not a Muppet, but is portrayed by a real, live goldfish (most likely, multiple goldfish over the course of the series).
When represented in books or toys, Dorothy often has a feminine appearance, including big eyelashes. This is also not typical for your average goldfish.
First introduced on "Elmo's World" in 1998, Dorothy has also made appearances in the main Sesame Street storyline, beginning in 2000, thus demonstrating her independent existence outside of Elmo's imagination. Episodes in which Dorothy has played a key role in the main street action include:
- Episode 3918 - Elmo takes Dorothy to Dr. Gina for a checkup.
- Episode 3938 - Maria takes care of Dorothy, Telly's hamster, Herry's bird, and Gabi's friend's rabbit, all while she's trying to work.
- Episode 4042 - Elmo must select a fish-sitter for Dorothy before accompanying Gordon to a sporting event.
- Episode 4058 - Dorothy is among the competitors vying for the title of "Best Pet in the World."
Ten years before Dorothy was introduced, Elmo had a pet fish named Barkley. Nine years afterwards, Elmo had another goldfish named Bubbles, who passed away, much to Elmo's despair. Telly and Miles gave him another goldfish in the same episode to cheer him up, in which Elmo names his third fish, "Miles-Telly".
- Where Is Elmo's Blanket? (1999)
- Look and Find Elmo (2002)
- Listen to Your Fish (2003)
- Elmo's World: Sports! (2004)
- Fun with Friends (2004)
- Animal Alphabet (2005)
- Elmo's Easy As ABC (2006)
- Elmo's Easy As 123 (2006)
- My First Book About Fish (2006)
- Elmo & Friends Picture Stories (2007)
- Friendly, Frosty Monsters (2007)
- What Makes Elmo Happy? (2008)
- Count to 10 (2009)
- Love, Elmo (2009)
- Elmo and Dorothy: Friends Forever! (2010)
- Imagine with Elmo (2011)