This session aims to bring together researchers studying different aspect of ”water” solubility in nominally anhydrous minerals (NAMs) with special respect to recent analytical and experimental developments. The successful special volume in Reviews in Mineralogy and Geochemistry dedicated to the same topic in 2006 marked an important milestone in integrating the state-of-the-art knowledge in the field. As a “follow up”, this session provides an excellent forum to discuss and present the progress that has been achieved since then. Applications of new analytical techniques or methods for characterising ”water” in NAMs are most welcome as these are fundamental for understanding physical and chemical properties of NAMs in more depth. Contributions addressing the incorporation and diffusion of ”water” in NAMs at different physico-chemical conditions are also invited. Additionally, it would be desirable to discuss the possibility of formulating (a) protocol(s) for the two, presently most employed techniques (FTIR and SIMS) because the lack of uniform data treatment often lead to non systematic discrepancies that prevent us from realizing the true systematics of “water” incorporation. These progresses are essential to quantify the water content of minerals from various geological settings and geodynamical histories. The session is expected to attract a considerable number of specialists and also may be of interest for a broader audience being one of the most developing fields in earth sciences.