Vertical integration
Vertical integration is the ownership of successive stages of a supply chain, from inputs through to distribution.
Every firm draws a line between what it makes and what it buys. Vertical integration is the decision to move that line.
Vertical integration is the ownership of successive stages of the supply chain, from raw inputs through production to distribution. A firm integrates backward when it takes over its suppliers, and forward when it takes over its distributors or retailers, bringing under one roof activities that could otherwise be transacted in the market.
Why own rather than buy
The classic case for integration is to secure supply, capture a supplier's or distributor's margin, coordinate tightly across stages, or protect quality and proprietary knowledge. When dealing with outside parties is costly, risky, or unreliable, owning the stage can be cheaper and safer than contracting for it. This is the logic of transaction cost economics: firms internalise activities when the market is a worse way to organise them.
The costs of owning
Integration is not free. It raises fixed costs and capital intensity, ties the firm to a captive supplier that may grow inefficient without market pressure, and reduces flexibility. An integrated firm can find itself defending an obsolete in-house stage long after the market has moved on, because exiting means writing off owned assets rather than simply switching suppliers.
The shifting line
The right degree of integration is not fixed; it moves with technology and markets. For decades carmakers integrated heavily; later many outsourced components to specialist suppliers who achieved scale across customers. The reverse can also happen when control of a critical stage becomes a source of advantage, as with firms that bring chip design or logistics back in-house.
The decision is best framed not as a matter of principle but of comparison: for this particular stage, today, is the firm a better operator than the market, and is the loss of flexibility worth the gain in control? The answer changes, which is why the make-or-buy line is redrawn far more often than most firms admit.