As part of the I Workshop One Health Barcelona , Dr. Carles Borrego, researcher at the Catalan Water Research Institute (ICRA-CERCA), has stressed the importance of understanding the relationship between antibiotic resistance and the environment. His speech, under the provocative title “One Health or One Waste?” , has highlighted how natural ecosystems become reservoirs of antibiotic-resistant genes due to contamination by pharmaceutical residues, a key aspect in addressing the global challenge of antimicrobial resistance. Borrego emphasized how aquatic and terrestrial ecosystems can act as reservoirs of antibiotic-resistant genes, a phenomenon that is accentuated by the presence of pharmaceutical pollutants in the environment. This relationship, he noted, is fundamental to a more comprehensive perspective in the fight against antimicrobial resistance, a growing threat that goes beyond human health and also affects animals and the natural environment. The I Workshop One Health Barcelona , under the motto “From theory to practice” , set out to promote a deeper understanding of the interconnection between human, animal and environmental health. The aim was to address these shared challenges in a practical way through interdisciplinary collaboration, with special emphasis on the real experiences of the professionals involved. The congress brought together experts from various fields to share both the successes and challenges of past projects, thus establishing a platform for learning from case studies in global health. During the workshop, participants highlighted the benefits of the One Health approach, which connects the health of people, animals and the environment. This approach is critical to disease prevention and control, as well as to developing practical and effective strategies for rapid response to outbreaks. In the long term, these types of initiatives can also generate a positive economic impact, reducing costs derived from treatments and minimizing economic consequences, such as the closure of industries or the impact on sectors such as tourism and trade. Attendees had the opportunity to collaborate and establish support networks, a key component in building a scientific and technical community that works beyond the congress on joint initiatives. This first edition of the Workshop One Health Barcelona is a step forward to promote innovation, creativity and interdisciplinary collaboration in the field of global health.