Understanding the interaction of a solute with the surrounding solvent molecules is essential to control reactivity in chemistry. When reactions are initiated by light, the dynamics can be studied by a number of ultrafast experimental techniques that provide information on the solute-solvent interactions over time. The evolution of the solute's electronic wave function can be inferred from methods such as transient absorption spectroscopy, time-resolved X-ray fluorescence or photoelectron spectroscopy. The solute's vibrational response can be investigated through ultrafast X-ray scattering experiments, which are also able to measure the solvent response occurring through libration and diffusion. Yet, obtaining time-resolved information on specific or strongly localized intermolecular interactions (such as hydrogen bonding), which influence both the nuclear and electronic solute properties on very short time scales, is particularly challenging.