The Strategy Kernel

WHY IT EXISTS Rumelt built the strategy kernel after observing that most documents labeled strategy are actually a wish list, a revenue target, a mission statement, and a stack of initiatives with no connective logic between them. He calls this bad strategy. The kernel gives a minimal, checkable structure for what a real strategy must contain, so a team can tell strategic thinking apart from restated ambition.

THE MENTAL MODEL Treat it like a medical treatment plan. A diagnosis names what is actually wrong, not just the symptom the patient complains about. A guiding policy is the doctor's overall approach to treating that diagnosis. Coherent action is the actual regimen, medication, therapy, follow up visits, carried out consistently with that approach. A plan built for an undiagnosed illness can still list sensible sounding actions, but it is not treatment, and a strategy without a diagnosis is not strategy.

HOW IT WORKS The kernel has three linked parts. Diagnosis simplifies a complicated situation into a clear, honest statement of the critical obstacle, specific enough to be wrong, not a restated goal; wanting more revenue is a goal, while losing deals because sales cannot explain the product's advantage over a specific competitor is a diagnosis. Guiding policy is the overall approach chosen to address that obstacle, and its job is to rule out a wide range of otherwise reasonable actions rather than pursuing everything at once. Coherent action is the concrete, coordinated set of steps, resource commitments, and policies that reinforce each other and are actually executable, rather than a list each department wrote independently.

WHEN IT MATTERS This matters most when reading or writing an actual strategy document, since it decides whether the document is executable or just motivational. Rumelt's named footgun is bad strategy: substituting a goal for a diagnosis, filling a template with ambitious language, or listing every good idea in the building as a bullet point with no prioritization, leaving different teams pulling in different directions while believing they are aligned.

ONE CONCRETE EXAMPLE A SaaS company announces its strategy as grow revenue 30 percent and become the most loved brand in the category, two goals with no diagnosis. Applying the kernel, the real diagnosis turns out to be that non technical buyers abandon a clunky onboarding flow in their first week. The guiding policy becomes win on time to first value for these users rather than competing on feature count, and coherent action bundles a redesigned onboarding flow, a support incentive tied to week one activation, and a deliberate pause on new advanced features for two quarters.