The past several years have witnessed a burgeoning of the research on halide perovskite photovoltaic (PV) materials. These materials are structurally distinct from all previous high-efficiency PV materials, such as Si, GaAs, CdTe, and CIGS. Recently, the halide perovskites have also been explored for other optoelectronic devices, such as LEDs. These breakthroughs have motivated us to study other perovskite materials that are potentially semiconductors, instead of dielectrics. Recently, we explored the chalcogenide perovskite materials in quest of suitable ones for PV applications. A number of promising candidates have been identified. In this talk, I will further explore two-dimensional chalcogenide perovskites. In particular, I will discuss the possibility of existence of such materials, including their structures, thermodynamic and kinetic stabilities from a density-functional-theory point of view. I will also discuss their electronic and optical properties in the context of nanoelectronic and optoelectronic applications.