The Intergovernmental Oceanographic Commission (IOC) has been involved for 50 years in promoting the close coordination needed to ensure comparability of oceanographic measurements. In particular, IOC played a key role in encouraging the development of chemical standards and reference materials for oceanic measurements. This paper briefly reviews this history, and also the early work of the author’s laboratory in producing reference materials for oceanic carbon dioxide measurements. The success of the latter program in improving the state of the art of such measurements encouraged others to develop, produce, and distribute additional reference materials for dissolved organic carbon, trace metals, and nutrients. The widespread use of these various reference materials is playing a significant role in ensuring the comparability of ocean data from a variety of laboratories, thus enabling the data to be put to use in global studies.

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