Rumsfeld Matrix

The Rumsfeld Matrix is a way of sorting what a team knows and does not know about a situation, so that its plans account for uncertainty instead of ignoring it. It divides knowledge into four categories: things we know we know, things we know we do not know, things we do not know we know and things we do not know we do not know. The last category, unknown unknowns, is the reason the matrix exists. Most planning deals well with known risks, but the events that derail strategies and projects are often the ones nobody thought to ask about.

The matrix takes its name from Donald Rumsfeld, then the US Secretary of Defense, who used the language of known knowns, known unknowns and unknown unknowns at a Pentagon press briefing in February 2002, in answer to a question about evidence on Iraq. The remark was widely mocked at first and later widely quoted. The ideas themselves were older: the terms were already in use in engineering, risk management and project planning, and the four-quadrant structure resembles the Johari window, a model of self-awareness that psychologists Joseph Luft and Harrington Ingham published in 1955. In business, the matrix is now used in strategy, risk management, project planning and decision-making.

The Four Quadrants

The matrix crosses two questions: whether we know something, and whether we are aware of our knowledge or lack of it.

Known Knowns

Facts the team knows and knows that it knows: established data, confirmed requirements, contractual terms and well-understood processes. These form the basis of a plan. The risk in this quadrant is overconfidence, since some known knowns turn out to be assumptions that were never tested.

Known Unknowns

Questions the team is aware of but cannot yet answer, such as how a competitor will respond, what a regulator will decide or how long a technical integration will take. This is the territory of conventional risk management. Known unknowns can be researched, estimated, tested with experiments or covered with contingency plans and buffers.

Unknown Knowns

Knowledge that exists but is not being used. It may sit with one person or team without reaching the people making the decision, or be so taken for granted that no one states it. The term also describes beliefs a group holds without examining them. Examples include a front-line team that knows customers dislike a planned change, or a lesson from a past failure that no one in the current project remembers. Surfacing unknown knowns is mostly a matter of asking the right people and making it safe for them to speak.

Unknown Unknowns

Risks and possibilities the team has not imagined at all. By definition they cannot be listed in advance, but organizations can reduce their number and their effect: by drawing on a wider range of perspectives, by studying failures in comparable situations, by watching for weak signals and by keeping the flexibility to respond when something unexpected happens.

How to Use the Rumsfeld Matrix

1. Frame the decision. Define the strategy, project or decision being examined and its time horizon.
2. Fill in the known knowns. List what the team is confident about, and challenge each item: is it established, or is it an assumption?
3. List the known unknowns. Capture the open questions and decide how to handle each one: research, run an experiment, set a contingency or accept the uncertainty.
4. Look for unknown knowns. Interview people outside the core team, such as customer-facing staff, partners and people who worked on similar efforts, and review lessons from past projects.
5. Probe for unknown unknowns. Use techniques such as a pre-mortem, in which the team imagines the plan has failed and works out why, and invite people with different backgrounds to challenge the plan.
6. Build the results into the plan. Move items into a risk register, add buffers or decision points and set triggers for revisiting the plan when key unknowns are resolved.

The aim is to move items across the matrix: to turn unknown unknowns into known unknowns that can be managed, and known unknowns into known knowns through research and testing.