Municipal wastewater contains a large range of excreted antibiotics and has therefore long been suspected to be a spawning ground for antibiotic-resistant bacteria. Now, a study led by a team from the University of Gothenburg and published in Nature Communications provides a more nuanced picture. By testing the potential of untreated municipal wastewater from 47 countries to select for resistant E. coli, the researchers show that while some samples indeed do so, most instead suppress them.