All those who had the pleasure of knowing Hani Mahmassani, who passed away on July 15, 2025 at the age of 69, will never forget him. He has left us with an incredible void, but lucky are we who were his friends, and/or his students, and/or colleagues, or collaborators.
Many thanks to Yue Wang of the University of Arizona, who prepared this poster notice for the Transportation Science and Logistics (TSL) Society memorial tribute event in honor of Hani Mahmassani that took place last week at the INFORMS Conference in Atlanta.
The session began with a Zoom presentation by Roberto Roberti of Italy, this year's recipient of the Stella Dafermos Mid-Career Award, and then it was time for our panel, which was chaired by Karen Smilowitz of Northwestern University, a colleague of Hani's.At the beginning, we gathered for a photo with Pat Mokhtarian, of Georgia Tech, who joined us. Pat was elected to the National Academy of Engineering, as Hani had been earlier.
Srinivas Peeta of Georgia Tech had prepared the nice collage poster of photos that some of us had also contributed to.
The talks were incredibly touching with Srinivas Peeta speaking about Hani, as his PhD advisor, and colleague, with numerous photos over the years of many luminaries in transportation science. He emphasized what a great researcher Hani was and also an outstanding organizer, integrator, and mentor.
In my presentation, which is available here: https://supernet.isenberg.umass.edu/visuals/Hani-Tribute-INFORMS-Nagurney.pdf, I included photos taken over many years of activities, including service ones, I had engaged in with Hani. So many memories came flooding back and I can hear his voice. Hani always inspired us to reach higher and to do more. He stretched us professionally and personally with his many kindnesses and support.
Marco Nie, a colleague of Hani's at Northwestern, had used ChatGPT for his presentation slides, and it was fascinating to see what was picked up by AI in terms of the contributions of Hani's research to transportation science, such as his work on bounded rationality and traffic assignment, and dynamic traffic network equilibrium.
Mike Hyland of UC Irvine, and a former PhD student of Hani's, spoke from the heart about how it was to work with Hani, who only slept a few hours a night. Hani was always willing to listen and to push the frontiers of transportation research and practice. He supervised over 75 PhD theses.
We then took the group photo below. Thanks to all who were able to join us for this touching memorial session in honor of Hani Mahmassani.
For the In Memoriam, co-authored by Karen Smilowitz and Marco Nie, and published in the journal Transportation Science, see here: https://pubsonline.informs.org/doi/10.1287/trsc.2025.memorial.v59.n6
The In Memoriam ends as follows: "In 1997, Hani wrote a tribute to Robert Herman in Transportation Science. He closed his tribute with the following words that ring so true to us as we remember Hani: “I will miss him, and so will many others, but will always know that I am a richer person for having known him.”"






