Hydrogen bond plays a crucial role in many areas of physics, chemistry, and biology. There is a vivid research going in this area of science. The aim of this issue is to present papers of leading scientists working in spectroscopic and computational aspects of hydrogen-bonded systems to share their knowledge on the state-of-the-art in this important branch of science and to present their recent scientific work.

Therefore, we invite investigators to contribute original research articles as well as review articles that will stimulate the continuing efforts to understand molecular interactions in hydrogen-bonded complexes, liquids, and solids; the development of experimental and theoretical strategies to treat hydrogen-bonded systems; the new evaluation of outcomes.

We are particularly interested in articles describing new experimental and theoretical methods for characterization of spectra, advances in molecular description of molecular interactions in hydrogen-bonded systems, new insights into molecular models, and current concepts in the treatment of small and large hydrogen-bonded systems. Potential topics include, but are not limited to:

• Recent developments in experimental and theoretical studies of hydrogen-bonded systems
• Advances in theoretical models of hydrogen bonds
• Spectroscopy of hydrogen bonds in excited electronic states
• Proton transfer in hydrogen-bonded complexes
• Photophysics of hydrogen-bonded systems
• Stability of hydrogen-bonded complexes
• Spectra of water, aqueous solutions, and ices
• Dynamical aspects of hydrogen bonding
• Cooperative interactions involving hydrogen bonds
• Unconventional hydrogen bonds