What is DDMRP (Demand-Driven MRP)?
A planning method that positions strategic inventory buffers and replenishes them based on actual demand rather than forecast-driven MRP calculations.
Definition
Demand-Driven Material Requirements Planning (DDMRP) is a planning methodology, formalized in the 2010s, that blends elements of MRP, lean, and theory of constraints to make supply chains more responsive and less nervous. Instead of pushing material from forecasts, DDMRP places strategically positioned stock buffers at key decoupling points and replenishes them based on actual consumption and a calculated net flow position. Buffers are sized using average daily usage, lead time, and variability, and are color-coded into zones (red, yellow, green) that signal when to reorder. The approach reduces the bullwhip effect and forecast nervousness that plague traditional MRP, while still planning beyond pure kanban for items with longer lead times.
How DDMRP Works in ERP
ERPs that support DDMRP let planners designate decoupling points, calculate buffer zones from usage and lead-time inputs, and generate replenishment based on the net flow equation of on-hand plus on-order minus qualified demand. Color-coded buffer status drives prioritized, demand-signaled order recommendations rather than forecast-exploded requirements. The system continuously recalculates buffers as demand and variability change and surfaces alerts when buffers are penetrated, giving planners a clear, exception-based view.
ERP Vendors with Strong DDMRP
Frequently Asked Questions
How is DDMRP different from traditional MRP?
Traditional MRP explodes a forecast and master schedule to push material through the supply chain, which can amplify variability and create nervousness when demand shifts. DDMRP positions strategic buffers at decoupling points and replenishes them based on actual demand and a net flow calculation, making supply more responsive and stable. In effect, DDMRP pulls to protect and replenish buffers rather than pushing to a forecast.
What are buffer zones in DDMRP?
DDMRP buffers are divided into color-coded zones, with red protecting against variability and lead-time risk, yellow covering demand over the replenishment cycle, and green setting the reorder frequency and order size. The zones are calculated from average daily usage, lead time, and variability factors. When the net flow position drops into a buffer, the system signals replenishment, giving planners a clear, visual, demand-driven priority.