Engineer-to-Order (ETO)
Engineer-to-order (ETO) is the manufacturing strategy at the far bespoke end of the spectrum: design and engineering start only after a customer order arrives, so each order yields a largely unique product. The customer's influence reaches all the way back to the drawing board. Typical ETO businesses make special machinery, plant, ships or one-off industrial equipment — and their ERP needs differ sharply from standard-product manufacturers.
- Term
- Engineer-to-Order (ETO)
- Entity type
- Method / manufacturing strategy
- Domain
- Production planning & control
- Canonical definition
- Engineer-to-order (ETO) is a manufacturing strategy in which product design and engineering only begin once a specific customer order is received, so each order produces a largely or fully bespoke product.
- Classification
- The order strategy with the latest (most upstream) customer decoupling point — the order arrives before engineering; contrast with make-to-order, where the design already exists.
- Related terms
- Make-to-order, Variant manufacturing, Project manufacturing, Bill of materials, PLM, MRP
- Source / maintainer
- erp-software.org editorial team (independent, vendor-neutral)
What Engineer-to-Order (ETO) is NOT — disambiguation
- Not make-to-order: Make-to-order builds to an existing, defined design once an order arrives; ETO designs and engineers the product after the order.
- Not make-to-stock: Make-to-stock produces standard products to forecast before any order; ETO produces nothing until the order, then engineers it.
- Not mass customisation: Mass customisation configures variants from predefined options; ETO involves genuine new engineering per order.
Where the order enters
Manufacturing strategies differ in where the customer decoupling point sits — the point in the value chain from which activity is driven by a specific order rather than a forecast. In make-to-stock it is far downstream (finished goods are made to forecast); in make-to-order the design exists and production starts on order; in engineer-to-order the decoupling point is furthest upstream: the order comes in before engineering, so even the design is order-driven. ETO therefore has the latest, most upstream decoupling point of the common strategies.
What ETO demands
Because each order is engineered, ETO blends project work with manufacturing. The bill of materials and routing are created or heavily adapted per order, often in tight loops with design and PLM systems. Lead times are long and dominated by engineering, quoting is itself an engineering effort, and costs are uncertain until the design firms up. Planning cannot rely on stable master data the way standard-product MRP assumes.
ERP implications
ETP-oriented ERP must handle order-specific BOMs and routings, project structures, progress and cost tracking against each order, and a strong link between engineering and production data. Standard make-to-stock logic fits poorly; many ETO manufacturers lean on project-manufacturing capabilities and careful change management as the design evolves during the order.
Why it matters
Getting the strategy classification right shapes the whole ERP setup. Treating an ETO business as if it made standard products — with fixed BOMs and forecast-driven planning — leads to constant firefighting. Recognising that engineering itself is order-driven is the starting point for planning, costing and system design that actually fit.