Measurements of Cefuroxime levels performed in dogs show a decrease against time in well perfused tissue similar to that in serum, while in bradytrophic tissue--such as bone and articular capsule--there is a distinct rise of these values in the time scale assessed. In similar investigations in man the higher levels in bradytrophic tissue are attributable to delayed elimination from the compact and spongy bone as compared to the serum. The effect on osteomyelitis, to be derived from this, is discussed.