The overall aim of this proposal is to identify two clinical M. abscessus isolates that were recently derived from cystic fibrosis, bronchiectasis or chronic obstructive pulmonary disease patients and are representative of the strains relevant in the present context so that they can be used as reference strains in research. The historical M. abscessus strain that is currently used as the default reference strain was isolated in 1953 from a knee abscess. Therefore, it is unknown how relevant the data obtained using this will be to pulmonary infections and drug susceptibilities to strains prevalent today. Our central hypothesis is that reference strain(s) should represent current clinical isolates. We postulate a relevant reference strain is necessary for rigorous research so that the data obtained will be more applicable to M. abscessus infections in cystic fibrosis, bronchiectasis and chronic obstructive pulmonary disease patients.