Gamma spectroscopy with a high resolution Ge(Li) detector is used to determine243Am by its 74.7-keV gamma transition in solutions containing much higher specific activities of other actinides and fission products. As little as 100 ppm of243Am relative to244Cm can be determined. A relative standard deviation of 1.4% was obtained for routine samples. The method is well suited for analytical control of curium process steps because of its simplicity, speed, and reliability.