Salicylic acid (SA) is a widely used herbal medicine and a major defense hormone in plants against pathogens and abiotic stresses. Over the past 30 years, modern technologies have revealed new research frontiers and surprises in understanding SA's effects on plant growth, development, and defense. This review updates recent advances in the understanding of SA metabolism, perception, and signal transduction mechanisms in plant immunity. SA executes its functions through intricate regulation at multiple steps, including local and systemic biosynthesis, perception by multiple cellular targets, and post-translational modifications of downstream signaling components. SA also impacts wider cellular functions through crosstalk with other plant hormones. The review highlights the role of SA in orchestrating complex post-translational modifications and the formation of biomolecular condensates that function as cellular signaling hubs. Future research directions include exploring SA functions in plant species where NPR proteins are less pronounced, such as rice, and understanding how SA is perceived and transduced in these species.Salicylic acid (SA) is a widely used herbal medicine and a major defense hormone in plants against pathogens and abiotic stresses. Over the past 30 years, modern technologies have revealed new research frontiers and surprises in understanding SA's effects on plant growth, development, and defense. This review updates recent advances in the understanding of SA metabolism, perception, and signal transduction mechanisms in plant immunity. SA executes its functions through intricate regulation at multiple steps, including local and systemic biosynthesis, perception by multiple cellular targets, and post-translational modifications of downstream signaling components. SA also impacts wider cellular functions through crosstalk with other plant hormones. The review highlights the role of SA in orchestrating complex post-translational modifications and the formation of biomolecular condensates that function as cellular signaling hubs. Future research directions include exploring SA functions in plant species where NPR proteins are less pronounced, such as rice, and understanding how SA is perceived and transduced in these species.