Justine M. Cassell (born March 19, 1960) is an American professor and researcher interested in human-human conversation, human-computer interaction, and storytelling.

She then spent a year as visiting faculty in the department of Computer and Information Science at the University of Pennsylvania, and moved from there to the MIT Media Lab, where she got tenure in 2001.

After leaving MIT, she became a full professor in the departments of Electrical Engineering and Computer Science, and Communication Studies at Northwestern University.

She designed a web-based storytelling system called "Renga, the Cyberstory" to help draw girls into new technology.

[7] In 1998 Cassell co-edited and co-wrote a volume called From Barbie to Mortal Kombat: Gender and Computer Games with Henry Jenkins.

One gets a sense of this insider view from looking at the 'talk page' of many articles, which rather than seeming like collaborations around the construction of knowledge, are full of descriptions of 'edit-warring' — where successive editors try to cancel each other's contributions out — and bitter, contentious arguments about the accuracy of conflicting points of view...However, it is still the case in American society that debate, contention, and vigorous defense of one's position is often still seen as a male stance, and women's use of these speech styles can call forth negative evaluations.

"[16] More recently, Cassell has built "socially-aware" conversational agents, capable of recognizing and engaging in rapport-building behaviors with people.

In 2017 her team was invited to build an example of this work, the Socially Aware Robot Assistant (SARA) for World Economic Forum attendees to interact – the first live demonstration of AI technology in the Davos Congress Center.

[17] As of January 2024, Cassell has been invited to speak about Artificial Intelligence at the World Economic Forum meetings in Davos 9 times.