Reactive astrogliosis, a widespread but poorly understood phenomenon in the central nervous system (CNS), involves astrocytes undergoing molecular and morphological changes. Recent advances using genetic tools have enabled the molecular dissection of its functions and mechanisms. Reactive astrogliosis can have both beneficial and detrimental effects, depending on the molecular signaling pathways involved. Reactive astrocytes may lose normal functions and gain abnormal effects, contributing to various disease processes. Astrocytes respond to CNS insults like infection, trauma, ischemia, and neurodegenerative disease through reactive astrogliosis, which includes scar formation. While scar formation has traditionally been viewed negatively, recent evidence suggests that reactive astrocytes also have essential beneficial roles in neural protection and repair. The article reviews signaling mechanisms regulating reactive astrogliosis and highlights potential therapeutic targets for neurological disorders. Reactive astrogliosis is a spectrum of changes in astrocytes in response to CNS injuries, ranging from mild to severe. It is regulated by context-specific signaling events and can lead to scar formation. The functional consequences of reactive astrogliosis vary depending on the type and severity of the insult. Reactive astrocytes can exert both beneficial and harmful effects, such as protecting neurons from excitotoxicity, oxidative stress, and inflammation, or contributing to neurodegeneration and chronic inflammation. Studies show that reactive astrocytes play critical roles in neural protection, repair, and regulation of CNS inflammation. They can protect neurons by clearing glutamate, reducing oxidative stress, and facilitating blood-brain barrier repair. However, they can also contribute to disease through loss of essential functions or gain of detrimental effects, such as promoting inflammation and impairing axon regeneration. The article discusses the molecular repertoire of reactive astrocytes, their triggers, and signaling mechanisms. It highlights the potential for identifying novel therapeutic targets by understanding the molecular mechanisms of reactive astrogliosis. Genetic manipulations and molecular techniques are enabling the dissection of reactive astrocyte biology in vivo. The findings suggest that reactive astrogliosis is a complex and multifaceted process with both beneficial and harmful effects, and that therapeutic strategies should target specific aspects of this process to promote neural repair and prevent disease.Reactive astrogliosis, a widespread but poorly understood phenomenon in the central nervous system (CNS), involves astrocytes undergoing molecular and morphological changes. Recent advances using genetic tools have enabled the molecular dissection of its functions and mechanisms. Reactive astrogliosis can have both beneficial and detrimental effects, depending on the molecular signaling pathways involved. Reactive astrocytes may lose normal functions and gain abnormal effects, contributing to various disease processes. Astrocytes respond to CNS insults like infection, trauma, ischemia, and neurodegenerative disease through reactive astrogliosis, which includes scar formation. While scar formation has traditionally been viewed negatively, recent evidence suggests that reactive astrocytes also have essential beneficial roles in neural protection and repair. The article reviews signaling mechanisms regulating reactive astrogliosis and highlights potential therapeutic targets for neurological disorders. Reactive astrogliosis is a spectrum of changes in astrocytes in response to CNS injuries, ranging from mild to severe. It is regulated by context-specific signaling events and can lead to scar formation. The functional consequences of reactive astrogliosis vary depending on the type and severity of the insult. Reactive astrocytes can exert both beneficial and harmful effects, such as protecting neurons from excitotoxicity, oxidative stress, and inflammation, or contributing to neurodegeneration and chronic inflammation. Studies show that reactive astrocytes play critical roles in neural protection, repair, and regulation of CNS inflammation. They can protect neurons by clearing glutamate, reducing oxidative stress, and facilitating blood-brain barrier repair. However, they can also contribute to disease through loss of essential functions or gain of detrimental effects, such as promoting inflammation and impairing axon regeneration. The article discusses the molecular repertoire of reactive astrocytes, their triggers, and signaling mechanisms. It highlights the potential for identifying novel therapeutic targets by understanding the molecular mechanisms of reactive astrogliosis. Genetic manipulations and molecular techniques are enabling the dissection of reactive astrocyte biology in vivo. The findings suggest that reactive astrogliosis is a complex and multifaceted process with both beneficial and harmful effects, and that therapeutic strategies should target specific aspects of this process to promote neural repair and prevent disease.