ATLAS performance for B physics

Since the publication of the ATLAS Technical Design Report, the ATLAS detector has undergone several changes that affect the B-physics programme. The new situation, together with the remarkable progress of the B-physics field in the last years, made the collaboration rethink about the strategy for B-physics measurements. The strategy of ATLAS for B-physics is explained. The implications on the ATLAS trigger are described. Finally, the detector and B-phycis performance are summarized.