The chapter discusses the evolving technologies and innovations in ammonia manufacturing and utilization, driven by the need for cleaner energy, agriculture, and chemical sectors. Ammonia, a "carbon-free fuel" due to its composition of nitrogen and hydrogen, is used in power generation, fertilizer production, and as a building block for various chemicals. The current state-of-the-art process, the Haber–Bosch process, produces significant carbon emissions, particularly from hydrogen production. "Brown Ammonia" refers to ammonia produced from fossil fuel-derived hydrogen, while "Grey Ammonia" is produced from methane-derived hydrogen. To reduce emissions, carbon capture and storage/utilization have been implemented, leading to the creation of "Turquoise" and "Blue" ammonia. The most advanced approach, "Green Ammonia," uses renewable electricity to produce hydrogen, aiming for near-zero emissions. However, this requires substantial reductions in grid carbon intensity. Overall, transitioning from brown and grey ammonia to green ammonia is crucial for achieving net-zero climate goals, but cost and sustainability assessments are essential to ensure feasibility.The chapter discusses the evolving technologies and innovations in ammonia manufacturing and utilization, driven by the need for cleaner energy, agriculture, and chemical sectors. Ammonia, a "carbon-free fuel" due to its composition of nitrogen and hydrogen, is used in power generation, fertilizer production, and as a building block for various chemicals. The current state-of-the-art process, the Haber–Bosch process, produces significant carbon emissions, particularly from hydrogen production. "Brown Ammonia" refers to ammonia produced from fossil fuel-derived hydrogen, while "Grey Ammonia" is produced from methane-derived hydrogen. To reduce emissions, carbon capture and storage/utilization have been implemented, leading to the creation of "Turquoise" and "Blue" ammonia. The most advanced approach, "Green Ammonia," uses renewable electricity to produce hydrogen, aiming for near-zero emissions. However, this requires substantial reductions in grid carbon intensity. Overall, transitioning from brown and grey ammonia to green ammonia is crucial for achieving net-zero climate goals, but cost and sustainability assessments are essential to ensure feasibility.