This report describes definitions, concepts and important parameters within B-detection capability. It provides a summary of current available B-detectors as well as ongoing research and development. Discussions regarding the near future development based on expected development are also included. The use of a B-detector alone is of relatively limited use. However, together with sampling and identification system, it provides the response time needed and helps optimizing the subsequent analysis process. The work is done partly as the result of a Nordic collaboration under NORDEFCO.