Pseudomonas aeruginosa is an opportunistic pathogen frequently associated with infections of immunocompromised patients. These infections, often refractory to antibiotic therapy, commonly present as biofilms that complicate and limit therapeutic options but represent cases in which the utility of phage therapy could be examined. Here, we describe laboratory experiments on a bacteriophage cocktail for the eradication of a P. aeruginosa biofilm, and experimental application of this cocktail in a human patient. Our in vitro experiments were designed to test the efficacy of our bacteriophage cocktail for the eradication of a P. aeruginosa biofilm grown on Dacron and Gore-Tex – two materials commonly used for indwelling medical prostheses. These assays revealed bacteriophage cocktail-Ceftazidime synergy, allowing us to prepare the bacteriophage cocktail for human application in an 81 year-old male with a chronic P. aeruginosa infection. This patient previously underwent a coronary artery bypass and aortic arch replacement with an aortic Dacron graft that was complicated by a mediastinal and graft infection. The patient returned to the operating room several times for debridement and washout of the infected chest wall. He eventually developed a thoracic abscess and associated fistula to the chest wall. He received intravenous ceftazidime for nearly two years, which suppressed the patient’s aortic graft infection but was unable to completely clear it. Because of the patient’s surgical history and medical condition, further elective surgical management was not an option due to the high mortality risk. We therefore attempted application of our bacteriophage cocktail via direct access to the patient’s thoracic abscess by needle puncture using image guidance. Development and characterization of the bacteriophage cocktail and its application will be discussed.