The article reviews the molecular regulation of stem cell quiescence, a state where cells remain undivided and quiescent for prolonged periods. Recent advances in adult stem cell isolation have revealed that quiescence is an actively maintained state, involving signaling pathways that keep cells poised for rapid activation. The review discusses the characteristics and regulation of quiescence, including the identification of quiescent stem cells, molecular signatures of quiescence, and specific properties that allow quiescent cells to survive over extended periods. It highlights the importance of transcriptional and epigenetic mechanisms, such as the role of p53, RB protein, CDK inhibitors, Notch signaling, and miRNAs in regulating quiescence. The article also explores survival mechanisms in quiescent cells, including protection from environmental stress, metabolic sensors, and DNA repair mechanisms. Finally, it proposes that quiescence is a 'poised state' rather than a dormant state, and discusses the implications for tissue regeneration and therapeutic strategies.The article reviews the molecular regulation of stem cell quiescence, a state where cells remain undivided and quiescent for prolonged periods. Recent advances in adult stem cell isolation have revealed that quiescence is an actively maintained state, involving signaling pathways that keep cells poised for rapid activation. The review discusses the characteristics and regulation of quiescence, including the identification of quiescent stem cells, molecular signatures of quiescence, and specific properties that allow quiescent cells to survive over extended periods. It highlights the importance of transcriptional and epigenetic mechanisms, such as the role of p53, RB protein, CDK inhibitors, Notch signaling, and miRNAs in regulating quiescence. The article also explores survival mechanisms in quiescent cells, including protection from environmental stress, metabolic sensors, and DNA repair mechanisms. Finally, it proposes that quiescence is a 'poised state' rather than a dormant state, and discusses the implications for tissue regeneration and therapeutic strategies.