Inductively coupled plasma optical emission spectrometry (ICP-AES) is an analytical technique that can be used to measure elements at trace levels in inorganic & organic samples such as metals, polymers, food, pharmaceuticals, environmental, agriculture oils or fuels. The technique offers a multi-element capability, robustness high dynamic range and low detection limits. Although older techniques such as atomic absorption and atomic emission are still in use by some laboratories, there has been a high shift toward ICP-AES, particularly in the last decade. As this shift is likely to continue, analyst should be aware of the analytical aspects of ICP-AES.