Nanofertilizers (NFs) are nano-sized chemical substances capable of delivering nutrients to plants for extended periods and with considerably higher efficiency as compared to conventional fertilizers. The application of nanoparticles in agriculture is fairly recent, however, has gained much interest from the scientific community due to spectacular advantages including, high efficiency, specificity, low dose, cost-effectiveness, and eco-friendly nature. Even though the mode of NFs application and their effectiveness is least studied, the reported literature unequivocally demonstrated that the nature of NFs, chemical composition, synthesis, and mode and time of their application significantly control their effectiveness and subsequent outcomes. This book chapter covers the fate of NFs in soil, their penetration, and translocation in plants, and their effect on yield production and quality. It further emphasizes the effectiveness of the mode of application (i.e., soil and foliar) as well as their comparative advantages and future perspectives.