Insight into the hydration of biomolecules and simple ions on a molecular level is important for understanding, e.g. the mechanisms of enzymatic reactions and of dissolution of minerals. Numerous powerful experimental probes have been developed for the study of hydration structure and hydrogen bond dynamics. Knowledge about how the electronic structure of solutions is affected by hydration interactions has been gained through photoelectron spectroscopy and X-ray spectroscopy. X-ray absorption (XA) spectroscopy exhibits a strong sensitivity to hydration, in particular hydrogen bonding, since the underlying core-excited states often involve extended unoccupied orbitals which are very sensitive to slight geometric changes. To date, most XA studies of aqueous solutions and protic solvents have been performed at synchrotron facilities, but recent development of high harmonic generation is enabling XA measurements using laboratory based sources. Together with improvement in sample delivery and measurement geometry using, e.g. liquid flatjets, accurate XA spectra can be acquired.