The International Water Association (IWA) has hosted 25 specialty conferences pertaining to biofilms since 1989; 11 of them were focused on biofilm reactors. Biofilm Reactor Technology and Design 2010, which was co-organized by IWA and the Water Environment Federation, was the most recent of these conferences to take place in the U.S.A. After 16 years, the 26th specialty conference in this series – IWA Biofilm Reactors 2026 –will return to the U.S.A. in Orange Beach, Alabama.