Gallium scintigraphy was performed in 54 consecutive patients hospitalized for exploration of fever or inflammation of unknown origin, in whom thorough initial exploration did not yield any clue. Only in 28 patients (51.8%) could a definite diagnosis be established. The positive gallium scintigraphy results were clinically rated as valuable, questionable or valueless according to their contribution to the diagnosis. Gallium scintigraphy was positive in 22 patients (40%) and deemed valuable in 13 patients (24%). A final diagnosis could be ascertained in 77% of the cases with a positive scintigram. In contrast a cause of fever or inflammation was found only in 34% of the cases with a negative scintigram. Gallium scintigraphy is valuable as an early localizing investigation rather than a last resort test in patients with fever or inflammation of unknown origin. A positive scintigram increases the chances of establishing a final diagnosis.