Pseudomonas aeruginosa (PA) is an opportunistic human pathogen. The WHO recently designated PA as a “critical priority pathogen” against which new antibiotic interventions are urgently needed. The biology of PA has been extensively studied in mono-species cultures, yet during many infection scenarios, the organism frequently finds itself sharing the niche with other microbial species. This is especially so in airways of people with cystic fibrosis (CF), where the organism co-habits with a veritable “zoo” of other microbes, including Gram-negative, Gram-positive and fungal species. The problem is that such microbial consortia are difficult to stably maintain in vitro. However, recent advances made in our laboratory have enabled us to co-culture PA with a variety of other microbes. Using this in vitro continuous-flow system, we can now begin exploring how inter-species interactions alter the biology of PA. We have uncovered strong evidence for extensive inter-species interactions between PA and its neighbours with an important affect on AMR. For instance, co-culturing PA with other microbes dramatically enhances its resistance to antibiotics; whereas the growth of PA in mono-species cultures is strongly affected by even one dose of an anti-pseudomonal antibiotic (e.g. colistin or ciprofloxacin). Based on the results, the presence of two other common CF-associated species, Staphylococcus aureus and Candida albicans, confers a much higher degree of protection against antibiotic treatment. The characteristics and the background of this phenomenon will be detailed in the presentation.