This chapter explores the origins and enduring impact of Kanban as a cornerstone of Lean manufacturing and its adaptation across diverse industries. Developed at Toyota in post-war Japan, Kanban grew from a simple system of visual cards to control parts flow into a powerful pull-based method that aligns production with actual demand. By signaling when work should begin and limiting work-in-progress, Kanban curbs overproduction, minimizes inventory, and reveals workflow blockages in real time. Its elegance lies in simplicity: rather than relying on complex forecasts, it uses clear visual cues and structured rules to synchronize tasks and empower frontline workers to resolve issues immediately. Over decades, the physical cardboard has evolved into digital Kanban platforms that integrate barcodes, RFID, and cloud dashboards, extending its reach into high-variability environments and enabling predictive analytics. Beyond manufacturing, Kanban has improved hospital supply chains, streamlined patient flow in emergency departments, and enhanced surgical scheduling, demonstrating its versatility in settings where responsiveness and waste elimination are critical. While successful implementation demands cultural change and ongoing coaching, organizations that embrace Kanban report lower inventory costs, faster turnaround times, higher quality, and greater staff engagement. Ultimately, Kanban remains a timeless framework for creating adaptive, transparent, and continuously improving systems.