Strategy.

The framework

1. 01

   Draw the chain — activities, not departments.

   List what your business actually does, in the order value flows: getting inputs in, turning them into the product, getting it out, selling it, and supporting the customer afterwards — then add the activities that hold the rest up: purchasing, technology, people, admin. Porter's insistence on activities rather than departments matters, because a department is a political unit and an activity is an economic one; 'marketing' is a floor of people, while 'producing the proposal that wins the deal' is a link you can cost, compare and improve. Keep the list to ten or twelve links — a chain with forty links is an org chart wearing a disguise.

2. 02

   Cost each link, then value each link — the two lists will not match.

   Work through the chain twice. First, allocate roughly where the money goes — which links consume the payroll, the tooling, the management attention. Then, separately, ask where the customer perceives the value: what they would name if you asked why they chose you and why they stayed. The gap between the two lists is the strategy conversation. Links that eat cost but create nothing a buyer notices are candidates for cutting or automation; links that customers rave about while you run them on scraps are underfunded advantages. Precision isn't the point — being roughly right about a link you've never examined beats being precisely ignorant of the whole chain.

3. 03

   Give every link a verdict: advantage, parity, or someone else's job.

   Advantage links are the two or three activities where you genuinely beat the alternatives — through lower cost, or through something buyers will pay more for — and they deserve your best people and a disproportionate share of investment. Parity links only need to be good enough that they never lose you a customer, which is a liberating standard: pursuing excellence in a parity link is cost without strategy. Everything else is a candidate for a specialist who performs that activity for many businesses and will always run it better and cheaper than you can. Most founders resist the parity verdict hardest, because it means saying out loud that some of what the team does merely needs to be adequate.

4. 04

   Look between the links — and beyond your own chain.

   Porter's subtler point is that advantage often lives in the linkages: how quality feedback reaches purchasing, how the sales conversation shapes what operations builds, how service intelligence flows back into the product. A competitor can copy a single activity by hiring or buying; copying the way your activities reinforce one another is far harder, which makes linkages the most defensible advantage you own. And your chain doesn't end at your walls — it plugs into your suppliers' chains upstream and your customer's chain downstream, and some of the cheapest margin you will ever find comes from making your link fit theirs better: fewer handovers, less rework, an output shaped for the next chain's input.