Millets are considered the most sustainable cereal crops due to their robust climate resilience, minimal irrigational requirements, rich nutritional profile, and excellent compatibility with conventional cereals like corn, rice, and wheat. The demand for millet grains and millet-based food products has been increasing globally since the year 2023 was declared as the international year of millets by the United Nations. Millet grains undergo several unit operations after harvesting before reaching the consumer. These include primary processing, which transforms harvested crops into food ingredients; secondary processing, which converts these ingredients into edible products; and tertiary processing, which focuses on producing convenience or premium foods. This chapter explores different primary, secondary, and tertiary processing operations in the realm of millets, their impact on key characteristics, recent technological advancements, and associated challenges. It offers valuable insights into various methods involved in millet processing that could benefit researchers as well as the millet processing industries.