The 9th International Conference on Algorithmic Decision Theory will be held in Paris on November 16-18, 2026. The general chairs are Brice Mayag and Paolo Viappiani, and the program chairs are Lirong Xia and Vincent Mousseau. ADT seeks to bring together researchers and practitioners coming from diverse areas of Computer Science, Economics, and Operations Research in order to improve the theory and practice of modern decision support. Abstracts are expected by May 4, 2026 May 18, 2026, and full papers by May 11, 2026 May 25, 2026. Please check the call for papers for details.