15th International Symposium on Aquatic Oligochaeta

This volume is the proceedings for the 15th International Symposium on Aquatic Oligochaeta (ISAO15), held in Brussels, Belgium, from the 19th to 24th of September 2022. Since the first ISAO meeting was hosted by Ralph Brinkhurst in Sidney, British Columbia, Canada in 1979, our meetings have been held without interruption every three years. Just as the years seemed to be passing peacefully and our 15th ISAO was slowly coming together, the SARS-Cov-2 epidemic came suddenly into our lives, causing a complete disruption in our way of life. Although our 15th triennial symposium had originally been scheduled to convene in September 2021, we were only able to meet after going through this ordeal, four long years after our last symposium in Hirosaki, Japan, in September 2018, which was a great moment for all those who attended. Although the virus was losing the battle or, waning, it still retained some medical challenges along with cultural and financial restrictions that prevented some of our colleagues from several countries from joining us.