Dear colleagues, This is the final call for registration for the 7th International Symposium on Microbial Sulfur Metabolism (ISMSM), which will take place in Lisbon, Portugal, from 17–20 March, 2026. This meeting will bring together researchers from across the globe to explore the latest advances in microbial sulfur cycling - from molecular mechanisms to ecological and environmental perspectives. The meeting will include keynote talks, selected oral presentations, poster sessions, and opportunities for informal discussion and networking. We encourage you to register and submit your abstract until 13rd February 2026. https://wmsm.itqb.unl.pt/registration/ For more information visit: https://wmsm.itqb.unl.pt/ We look forward to welcoming you in Lisbon next March! The 7th ISMSM Organizing Committee Inês Cardoso Pereira, Filipa Sousa, José Artur Brito, Andreia Pimenta and Américo Duarte [email protected] --