
The U of T Engineering community is mourning the loss of Professor Dionne Aleman, who passed on October 21, 2025. Her passing came after a long illness, throughout which she was supported by the care of an incredible team, including her family, friends and colleagues.
Born in Miami, Fla., Professor Aleman completed her BSc, MSc and PhD at the University of Florida, studying industrial and systems engineering. She joined U of T’s Department of Mechanical & Industrial Engineering in 2007 and quickly became a much-respected member of the community.
Her work focused on the application of operations research to medical and healthcare systems to improve the quality, timeliness, and efficiency of care. This included everything from modelling the spread of pandemic diseases in urban populations to using simulations and machine learning to design and validate radiation therapy treatment plans.
Insights from Professor Aleman’s research continue to inspire new ways to improve hospital surgical scheduling and enhance organ transplant matches, leading to better outcomes and longer, healthier lives for people everywhere.
In addition to being a brilliant researcher and professor, Professor Aleman served as Associate Dean, Cross-Disciplinary Programs, Dean’s Advisor on 2SLGBTQ+ Initiatives, and was faculty co-chair of the Engineering Positive Space Committee. Her advocacy on behalf of the causes she believed in was admired across U of T, especially in her home Faculty of Engineering & Applied Science. Since her passing, the Faculty has received an outpouring of thoughtful messages from students, staff, faculty and alumni reflecting on her lasting impact.
Professor Aleman’s impressive achievements were only exceeded by her devotion to her family, including her wife, Nancy Huang, and son, Roberto Aleman. She is also survived by her sister, Erica Garriss, mother, Sandra Horwitz, and extended family and friends worldwide. Dionne was predeceased by her father, Roberto Aleman.
At U of T Engineering and beyond, well-known for her love of sports, fast cars, outdoor adventure and exploring new places. She reflected on many of these passions, and on her work in general, in a conversation with Dean Yip recorded in 2022. Professor Aleman will be missed immensely for her passion, advocacy and dedication.
To honour Professor Aleman’s memory and legacy, a memorial will take place on Wednesday, November 26 from 4:00-6:00 pm at the Myhal Centre for Engineering Innovation and Entrepreneurship. To attend please RSVP at: Remembering Professor Dionne Aleman – Department of Mechanical & Industrial Engineering
In honour of Professor Aleman’s impactful contributions across U of T, the Department is collecting donations in support of students and the 2SLGBTQ+ engineering community. Please visit University of Toronto if you would like to add your support to Professor Aleman’s work and legacy.
Read more about Professor Aleman’s life and family in her obituary.