Read an industry's structure through Porter's Five Forces with documented signals per rating, ending at the profit pool. Use when weighing market entry or when margins erode and nobody can say why.

Porter's Five Forces (Evidence Cited) Purpose Read an industry's structure through Porter's Five Forces, with evidence: search plan → force by force ratings with signals → profit pool implication → next step options. Each force — competitive rivalry, threat of new entrants, threat of substitutes, buyer power, supplier power — is rated weak/moderate/strong and justified with documented signals, because a rating without signals is vibes. The analysis closes where it should have been aiming all along: where the profit pool sits and who is squeezing it. Five forces is an argument about where margin goes, not a diagram for slide four. Input Works best with: the industry or segment, named as precisely as you can ("clinical data management SaaS," not "healthcare"), and the decision this analysis should support . Also useful: a geographic boundary if the structure differs by region, and a [ market landscape scan ](../market landscape scan/SKILL.md) in session — the forces read builds on it and searches only gaps. Input supplied inline with the invocation — text after the skill name, a pasted context dump, or an appended ARGUMENTS: line — counts as answers already given. Use it against the question budget; don't re ask. Arriving empty handed? That works too. The skill opens with at most 3 questions (segment, decision, boundary) and proceeds on labeled assumptions if they go unanswered. Example invocation: Five forces on mid market field service management software, North America — decision: whether we enter or partner. Key Concepts Governing protocol: honors the [ autonomous investigation ](../autonomous investigation/SKILL.md) contract — question budget of 3, search plan gate, Fact/Inference/Assumption labels, Just Enough Mode (2 4 signals per force), stable schema, 4 option Final Step. Disciplines: FININT (concentration, margins, filings) + OSINT (analyst coverage, trade press) per [ intelligence collection disciplines ](../intelligence collection disciplines/SKILL.md). The framework (Porter, 1979): industry profitability is determined by five structural forces, not by how hard incumbents work. Rivalry sets the intensity of margin competition; entry threat caps pricing; substitutes cap value; buyer power extracts margin downstream; supplier power extracts it upstream. Structure explains what negotiation skill cannot: pricing power is structural. Ratings must survive "how do you know?" Each weak/moderate/strong rating stands on documented signals — concentration data, switching costs, entry examples and how they fared, substitute adoption curves, margin trends. Forces with signals is the difference between naming a framework and using one. AI driven substitution is a named candidate, always. In most knowledge industries it is now the substitute threat; assess it explicitly in the substitutes force rather than letting the analysis pretend it's 2015. Supplier power gets the same modern read: cloud, model, and platform dependencies are supplier concentration. Industry, not player: this reads what the structure does to everyone who plays. [ swot analysis ](../swot analysis/SKILL.md) reads one company's position within it. When NOT to use: nascent categories with no stable structure — the forces are still forming; run the landscape scan and revisit. Do not invent list: market share, margin data, entrant names, funding rounds, adoption figures. Application 1. Credit inline context , then ask only the unanswered questions (max 3): 1. Which industry or segment, precisely? 2. What decision should this support? 3. Any geographic boundary? 2. Show the 3 bullet search plan — what you'll search per force, source types (filings, analyst coverage, trade press, pricing pages, funding databases), fact/inference separation. Continue unless revised. If a landscape scan is in session, build on it; search only gaps. 3. Rate each force with signals, then emit the schema below exactly. Output schema (do not reorder) ~~~markdown Five Forces: [Industry / Segment] As of date: Boundary: Decision supported: 1. Competitive Rivalry — [weak / moderate / strong] Signals: [concentration, growth rate, differentiation, exit barriers — each with URL + label] What it means here: [one sentence] 2. Threat of New Entrants — [weak / moderate / strong] Signals: [entry barriers, capital needs, recent entrants and how they fared, regulation — each with URL + label] What it means here: [one sentence] 3. Threat of Substitutes — [weak / moderate / strong] Signals: [substitute adoption, price performance trajectory, switching evidence — each with URL + label] AI driven substitution, named and assessed: [labeled] What it means here: [one sentence] 4. Buyer Power — [weak / moderate / strong] Signals: [buyer concentration, switching costs, price transparency, backward integration examples — URL + label] What it means here: [one sentence] 5. Supplier Power — [weak / moderate / strong] Signals: [supplier concentration (including cloud/model/platform dependencies), input differentiation — URL + label] What it means here: [one sentence] 6. The Profit Pool (the "so what") Where margin sits today, and the force squeezing it: [labeled] Structure trend: [tightening / loosening, on what evidence] For your decision: [2 sentences tying structure to the decision named above] Assumptions to Validate [Assumption 1] / [Assumption 2] / [Assumption 3] ~~~ A copy/paste fill in version of this schema, with quality checks, lives in [ template.md ](template.md). Final Step (offer exactly 4 options) 1. Trace the strongest force into your strategy's exposed assumptions 2. Run [ market landscape scan ](../market landscape scan/SKILL.md) to name the players behind each force 3. Feed the profit pool read into an Ansoff growth options analysis ([ ansoff matrix ](../ansoff matrix/SKILL.md)) 4. Schedule ready version: which force signals should a re run watch? Accept 1 , 2 , 3 , 4 , 1 and 3 , Verbose Mode , or a custom path. Examples A rating that survives "how do you know?" (fictional): 4. Buyer Power — strong Signals: top 10 buyers account for ~60% of segment spend — Fact ([trade association data, URL]); three publicized incumbent to rival switches in 18 months with no reported penalty — Fact ([press coverage, URLs]); public rate cards make pricing fully transparent — Fact ([vendor pricing pages]); one major buyer built the capability in house — Fact ([their engineering blog, URL]) What it means here: buyers can credibly threaten to leave or build, so list price integrity is an illusion in this segment — discounting pressure is structural, not a sales discipline problem. The profit pool close doing its job: rivalry moderate, entrants weak, substitutes strong (AI agents absorbing the low complexity tier), buyers strong, suppliers moderate. The pool sits in the regulated high complexity tier — the only place two strong forces don't reach — Inference . For the entry decision: enter only via the regulated tier; the volume tier's margin is already spoken for by buyers below and AI substitution above. See [ examples/sample.md ](examples/sample.md) for a complete worked five forces read (fictional FSM software market) that builds on the market landscape scan example and lands at a profit pool close that changes the decision. [ examples/sample industrial.md ](examples/sample industrial.md) shows the forces inverting in an industrial market — read both to see the framework adapt instead of recite. Common Pitfalls Ratings as vibes. "Rivalry: strong" because it feels crowded. Every rating stands on signals with URLs, or the whole exercise is a diagram. Skipping the AI substitute. Assessing substitutes as adjacent products while an AI workflow eats the category's low end. Name it and rate it, even when the rating is "weak — for now." Confusing competitors with structure. Listing who plays (that's the landscape scan) instead of what the structure does to everyone who plays. The forces are about margin physics, not rosters. No profit pool close. Five rated forces and no answer to "where does margin go?" The close is the analysis; everything above it is evidence assembly. Forcing structure onto a nascent category. Rating forces that haven't formed yet produces confident noise. Say "still forming," scan the landscape, revisit in two quarters. References [ autonomous investigation ](../autonomous investigation/SKILL.md) (Workflow) — the governing protocol [ intelligence collection disciplines ](../intelligence collection disciplines/SKILL.md) (Component) — FININT/OSINT sources behind the signals [ market landscape scan ](../market landscape scan/SKILL.md) (Workflow) — who plays; this skill asks what the structure does to them [ swot analysis ](../swot analysis/SKILL.md) (Workflow) — one company's position within the structure [ ansoff matrix ](../ansoff matrix/SKILL.md) (Workflow) — growth options informed by the profit pool read Michael E. Porter, "How Competitive Forces Shape Strategy" (Harvard Business Review, 1979) Adapted from market intelligence/porters five forces prompt.md in the https://github.com/deanpeters/product manager prompts repo.

porters-five-forces