The regular increase of drug-resistant pathogens has been a major force in the renewed interest in the use of bacteriophages as therapeutics. In addition to experience acquired in eastern Europe where bacteriophages have been used to treat bacterial infections in humans, in Western countries only experimental models have been developed until recently. The Gram-negative bacterium Pseudomonas aeruginosa is an opportunistic pathogen causing particularly severe infections in cystic fibrosis patients. Several experimental models in mice have yielded encouraging results for the use of bacteriophages to treat or prevent septicemia, skin and lungs infections caused by P. aeruginosa. Now, a phase II clinical trial conducted in the United Kingdom provides evidence for the efficacy of bacteriophage treatments in chronic otitis due to antibiotic-resistant P. aeruginosa strains. Together with experimental models, these results provide an incentive to develop more research and clinical studies to fully appreciate the benefits of the use of bacteriophages in medicine.