In this study, the current state of groundwater development and use and groundwater quality has been examined based on official groundwater data collected from the Republic of Korea. The groundwater data indicate a steady increase in the number of groundwater wells and an increase in groundwater pumping. The well diameters also increase with increasing well depth, owing to the development of drilling technology. Although groundwater is predominantly used for agricultural and living purposes, the former has recently outnumbered the latter. According to the groundwater quality monitoring stations covering the entire country, the groundwater levels, dissolved oxygen, and oxidation-reduction potential decrease with a steady increase in the water temperature, pH, and electrical conductivity, indicating an aggravating groundwater environment in this region. The most concerning contaminants found are nitrate, ammonia, arsenic, zinc, toluene, xylene, chloroform, and fluoride. Thus, based on these observations, we propose three essential tasks for sustainable groundwater use: a paradigm shift in groundwater management, conjunctive use and integrated management of groundwater and stream water, and groundwater governance and data quality control. [ABSTRACT FROM AUTHOR]