The article reviews the process of nitrate assimilation in plants, focusing on how plants acquire and utilize nitrate, a critical nutrient. Plants must compete for nitrogen in the soil and lose it when crops are harvested. They have evolved mechanisms to acquire and use various forms of nitrogen, including inorganic (nitrate, ammonia) and organic (urea) forms. Legumes can also fix nitrogen gas with symbiotic bacteria. The review highlights two key questions: how plants acquire optimal nitrate levels and how nitrate assimilation integrates into plant metabolism. Nitrate is taken up by plants through a versatile and robust transport system, driven by proton gradients. Once taken up, nitrate is reduced to nitrite and then to ammonia, which is fixed into carbon. The regulatory network that coordinates these steps is responsive to internal and external signals. Genetic analysis has been crucial in understanding nitrate assimilation, with mutants blocked in the pathway being rescued by providing ammonia. Recent molecular advances have identified genes and mechanisms responsible for nitrate uptake, reduction, and regulation. The article also discusses the role of nitrate as a signal for regulating nitrate assimilation, influenced by light, cytokinins, CO2 levels, circadian rhythms, and carbon and nitrogen metabolites. Post-transcriptional regulation, such as phosphorylation, plays a significant role in modulating nitrate reductase activity. The article concludes by discussing future prospects, including the potential use of nitrate assimilation genes in biotechnology and the engineering of crop plants to reduce nitrogen fertilizer requirements.The article reviews the process of nitrate assimilation in plants, focusing on how plants acquire and utilize nitrate, a critical nutrient. Plants must compete for nitrogen in the soil and lose it when crops are harvested. They have evolved mechanisms to acquire and use various forms of nitrogen, including inorganic (nitrate, ammonia) and organic (urea) forms. Legumes can also fix nitrogen gas with symbiotic bacteria. The review highlights two key questions: how plants acquire optimal nitrate levels and how nitrate assimilation integrates into plant metabolism. Nitrate is taken up by plants through a versatile and robust transport system, driven by proton gradients. Once taken up, nitrate is reduced to nitrite and then to ammonia, which is fixed into carbon. The regulatory network that coordinates these steps is responsive to internal and external signals. Genetic analysis has been crucial in understanding nitrate assimilation, with mutants blocked in the pathway being rescued by providing ammonia. Recent molecular advances have identified genes and mechanisms responsible for nitrate uptake, reduction, and regulation. The article also discusses the role of nitrate as a signal for regulating nitrate assimilation, influenced by light, cytokinins, CO2 levels, circadian rhythms, and carbon and nitrogen metabolites. Post-transcriptional regulation, such as phosphorylation, plays a significant role in modulating nitrate reductase activity. The article concludes by discussing future prospects, including the potential use of nitrate assimilation genes in biotechnology and the engineering of crop plants to reduce nitrogen fertilizer requirements.