Infectious diseases by opportunistic pathogens such as Pseudomonas aeruginosa and Burkholderia cenocepacia retain a prominent position as a major worldwide cause of morbidity and mortality in a wide range of patients. Once easily mastered through the administration of antibiotics, severe hospital- and community-acquired bacterial infections are on a sharp rise in Europe due to increasing resistance against available antibiotics. At the same time, the drug development pipeline for new antibiotics is virtually empty because of a lack of incentives for the pharmaceutical industry to invest in this field. In the longer term perspective, difficulties to effectively treat bacterial infections pose a threat to many modern diagnostic and treatment modalities.