The electrochemistry community provides the largest number of users of experimental information obtained at solid-liquid interfaces. Molecular scale surface science studies have been carried out mostly at solid-gas and solid-vacuum interfaces, although recently several optical and scanning tunneling techniques have become available that can scrutinize solid-liquid interfaces on the molecular level as well. In order to correlate structure and chemical behavior at solid-liquid and solid-gas interfaces, we suggest investigations of the same or similar systems in sequence at the solid-gas, solid-liquid, solid-solvent, and reactant interfaces, and solid-solvent and reactant interfaces with an external potential. In this paper we review the information accumulated from solid-gas interface studies on the effect of changing coverage, on bonding, and on trends of bonding across the periodic table. We discuss what is known about the surface structure, the surface chemical bond, the dynamics of surface atoms (diffusion, growth), and the reactivity of metal surfaces from solid-gas interface studies. In each section the available solid-liquid interface studies are also indicated. We hope to provide directions for future studies for those interested in correlating phenomena at solid-liquid and solid-gas interfaces.