Solar-thermal desalination devices based on interfacial vapor generation rely on heat localization over the interface instead of heating the bulk of the liquid and thus perform better than traditional solar stills. The enhancement in their performance arises from an efficient vapor generation rate. The idea of interfacial vapor generation is to improve two critical parameters: solar absorptivity and solar-to-vapor conversion efficiency. In this chapter, the three-layer strategy of interfacial vapor generation is first introduced. The significance and role of these three layers and the research methodologies are discussed next. However, long-term reliability and latent heat recovery to enhance productivity remains a bottleneck for making the concept commercially viable. Strategies adopted in the literature to address the problem of salt accumulation are first categorized, and their merits and demerits are delineated. Potable water productivity depends not only on efficient vapor generation but also on the condensation strategies adopted. Approaches adopted to enhance the condensation rate and methodologies implemented to recover latent heat are described. The chapter closes with a brief discussion on mathematical modeling, both at micro and macro scales, of the relevant transport processes.