Lean scheduling is the heartbeat of lean system. It is crucial to maintaining production line balance, parts movements, dynamic inventory control (effective and accurate min/max scheme), and minimizing inventory levels. Different business units or departments often require the same part. Many companies do not have a priority scheme for sharing parts and part fulfillment thereafter. Optimal Lean Scheduling (OLS) technique will achieve most effective priority scheme and inventory transparency to multiusers in the system. OLS combines theory of constraints, Kanban, and real time demand driven techniques to create a simple, visible, flexible, accurate, and fast systemic solution to scheduling. It has been successfully used by companies with single location or multi-national locations with complex organizational structure.