Decision-making & prioritisation
Six Thinking Hats
De Bono's method for splitting a group's thinking into six deliberate modes, worn one at a time so the whole room examines facts, feelings, risks, benefits and new ideas together, with a blue hat running the sequence. It replaces adversarial debate with scheduled, parallel focus.
Also known as Parallel thinking, De Bono's hats. First set out by Edward de Bono in 1985; the primary source is cited in full below.
- Format
- Checklist / audit
- Level
- Team
- Best for
- Evaluate options
- Decision stage
- Explore options · Decide
- Difficulty
- Introductory
- Time to apply
- A facilitated session of 45 to 90 minutes; minutes more to plan the sequence.
Plate · The model
The components
Blue hat: process control
The organising hat, usually held by the chair or facilitator. It defines the focus, sets and polices the sequence, calls for summaries and closes with conclusions and next steps. De Bono compares it to the conductor of the orchestra.
Signals of strength
What exactly are we thinking about · Which hat comes next and why · What has this mode produced · What is decided and who does what
White hat: information
Neutral attention to data: what is known, what is missing, how it could be obtained. Claims are separated from checked facts, and gaps are recorded rather than papered over.
Signals of strength
What do we actually know · What is the source and how good is it · What information is missing · How would we get it and by when
Red hat: feelings
Licensed intuition. Participants state emotions, hunches and gut reactions with no justification required or permitted. It surfaces what would otherwise leak into the discussion disguised as logic.
Signals of strength
My instinct says · How do we feel about this right now · No reasons given, none asked for · Kept short and revisited later if feelings shift
Black hat: caution
Critical judgement: risks, flaws, obstacles and reasons the proposal may fail or not fit. De Bono calls it perhaps the most valuable hat and also the most abused, because it is the mode educated people default to.
Signals of strength
What could go wrong and why · Where does this conflict with experience, policy or fact · What are we assuming that may not hold · Criticism of the idea, never the person
Yellow hat: benefits
Disciplined optimism: the value in the proposal and the grounds for believing in it. Yellow-hat thinking must give reasons; it is a search for feasibility and benefit, not cheerleading.
Signals of strength
What is the value and to whom · Under what conditions would this work well · What is the best defensible case · Why do we believe the benefit is real
Green hat: creativity
Generative thinking: alternatives, modifications, provocations and ways around the black hat's obstacles. The hat creates formal space for ideas that would be shot down on arrival in normal debate.
Signals of strength
What else could we do · How could we overcome the flagged risks · What would a deliberately provocative version look like · No evaluation while ideas are being generated
When it earns its keep
- A decision meeting keeps collapsing into advocacy, where positions were fixed before the evidence was heard and every point is a move in an argument.
- Hierarchy or politeness is suppressing candour, and you need a device that makes caution or emotion legitimate for everyone at once, including the boss.
- An option is being evaluated lopsidedly, all enthusiasm or all objection, and you want the group to visit every mode of assessment on the record.
- You chair recurring forums, such as a leadership group, where a repeatable meeting discipline is worth more than any single decision.
And when it doesn't
- The decision needs quantitative comparison of options against weighted criteria. The hats structure discussion, not evaluation; use a decision matrix for the arithmetic.
- The group is one or two people. The method's value is synchronising many heads; solo, a simple checklist of the six perspectives does the job without theatre.
- The real problem is missing information rather than unstructured discussion. A white-hat session cannot conjure data nobody has collected.
- Genuine conflict of interest divides the room. Parallel thinking assumes participants will honestly work each mode; it cannot referee a negotiation.
How to run it
Before starting, gather the inputs the analysis depends on:
- A clearly framed question or option to think about, agreed before any hat goes on.
- A facilitator willing to enforce the current mode, because the method fails politely and invisibly when people argue under cover of the wrong hat.
- The relevant information to hand for the white-hat pass, or an honest record of what is missing.
- A hat sequence chosen for the task, since de Bono is explicit that the order should vary with the purpose of the session.
- 1
Frame the question and set the sequence
Open under the blue hat. State precisely what is being thought about and agree the order of hats for this session. A common evaluation sequence is blue, white, yellow, black, red, blue, but de Bono treats the programme as a design choice, not a ritual.
- 2
Work each hat in turn, whole group together
Everyone wears the same hat at the same time. This is the parallel-thinking core: nobody is the critic while someone else is the advocate, so ego detaches from position and the room's full intelligence points one way at a time.
- 3
Keep contributions in mode
The facilitator redirects out-of-mode remarks by naming the hat, which de Bono designed as a face-saving correction: 'that is good black-hat thinking, hold it for later' lands more easily than 'stop being negative'.
- 4
Timebox the red hat short
Feelings are stated without justification, typically thirty seconds per person. The red hat legitimises intuition precisely by forbidding argument about it; letting people rationalise their gut defeats the point.
- 5
Close under the blue hat
Summarise what each mode produced, state the decision or next steps, and record what the black hat flagged that must be mitigated. A hats session that ends without a blue-hat synthesis was a conversation, not a method.
Reading the result
A structured record of the group's thinking on one question: the facts and gaps, the stated feelings, the risks, the grounded benefits, the new options generated, and a blue-hat synthesis stating the decision and actions.
- Weigh the black and yellow hats against each other only after both are complete; the method's promise is that each was produced with the whole group's effort, so neither is a faction's brief.
- Treat the red-hat record as data about the room, not about the proposal. Strong feelings against a well-supported option predict implementation trouble even if the decision goes ahead.
- A thin green-hat section is a warning: the group evaluated what was put in front of it and generated nothing, which usually means the framing arrived pre-decided.
A worked example
A ferry operator's leadership group examines chartering a fast catamaran
The leadership group of a Scottish island ferry operator meets to consider chartering a fast catamaran for the summer season to relieve its ageing second vessel, at a charter cost of roughly £1.8m against an uncertain uplift in passenger revenue. Previous discussions have split the room: operations wants the charter, finance calls it a luxury. The chief executive runs the meeting as a hats session with the finance director holding the blue hat.
- Blue hat: process control
- The question is fixed as 'should we charter the catamaran for the coming season', explicitly excluding the separate fleet-replacement decision. Sequence agreed: white, yellow, black, green, red, blue. Forty-five minutes total.
- White hat: information
- Known: the second vessel lost 31 sailing days last summer to breakdowns; charter quote is £1.8m for five months; the catamaran cannot berth at the smallest of the three harbours at low tide. Missing: reliable demand forecast for added capacity, and the penalty terms for early charter termination. Both gaps assigned owners.
- Yellow hat: benefits
- Even the sceptics build the case: cancellations are the biggest driver of complaints and lost islander goodwill; a reliable summer could recover the tourism traffic lost to the air service; crews get relief from firefighting; the charter is a cheap trial of catamaran operations before any purchase decision.
- Black hat: caution
- Even the enthusiasts work the risks: the low-tide berthing restriction cuts the usable timetable at exactly the peak sailings; charter plus fuel likely exceeds any plausible revenue uplift in year one; crew familiarisation on a new vessel type early in the season is a safety and punctuality risk; a good summer could make the case for fleet renewal look weaker to the funder than it is.
- Green hat: creativity
- Options generated: charter for the six peak weeks only; negotiate a charter with a purchase option so the trial feeds the renewal case; timetable the catamaran on the two deep-water routes only and redeploy the old vessel to the third; approach the tourism board to part-fund the trial as a visitor-economy pilot.
- Red hat: feelings
- Thirty seconds each. Operations director: relieved the risks were finally aired without it being a fight. Finance director: still uneasy at £1.8m but comfortable at a shorter charter. Harbour master: quietly excited. Chief executive: wary of doing nothing for another winter.
The read. The blue-hat close committed the group to pursuing the six-week peak charter with a purchase option, conditional on the two white-hat gaps being closed within a fortnight. The honest reading is that the hats did not produce the answer, the green hat's shorter-charter option did, and it only surfaced because the black-hat pass had made the full-season version indefensible to its own sponsors first. What the method demonstrably changed was the meeting: the same people who had deadlocked twice reached a committed position in under an hour.
Pitfalls
- Running the hats as personality types, assigning the black hat to the resident pessimist. The entire mechanism is that everyone wears every hat; casting roles rebuilds the adversarial meeting with props.
- Letting the red hat become an argument. The moment feelings need justifying, participants stop reporting them honestly.
- Using the black hat as a veto rather than a mode. Caution is one input to the blue-hat synthesis; a risk register is not a decision.
- Treating the standard sequence as sacred. A creativity session should lead with green; an evaluation session with white. The order is a design decision the blue hat must own.
- Deploying the method on a pre-made decision to manufacture consent. Groups detect this quickly and the device is spent thereafter.
What the critics say
The controlled-evidence base for de Bono's thinking tools is thin. Moseley and colleagues' systematic review of thinking frameworks found sparse research evidence that training in de Bono's tools produces generalised improvements in thinking, with support resting largely on anecdote and unpublished reports, and de Bono himself showed little interest in formal evaluation of efficacy.
Moseley, D., Baumfield, V., Elliott, J., Gregson, M., Higgins, S., Miller, J. and Newton, D. P. (2005) Frameworks for Thinking: A Handbook for Teaching and Learning. Cambridge: Cambridge University Press.
The method's premise that criticism should be scheduled out of idea generation is contradicted by experimental work on group creativity: Nemeth and colleagues found that groups encouraged to debate and criticise produced more ideas than groups instructed not to criticise, suggesting that synchronised, dissent-free modes may cost the group exactly the friction that improves its thinking.
Nemeth, C. J., Personnaz, B., Personnaz, M. and Goncalo, J. A. (2004) 'The liberating role of conflict in group creativity: a study in two countries', European Journal of Social Psychology, 34(4), 365-374.
Marching the whole room through one mode at a time creates a groupthink-by-sequence risk: a strong early yellow-hat consensus, or a chair who times the black hat short, can shape what members are willing to say in later modes, and the method gives the blue-hat holder considerable unexamined power over the outcome.
Sources and further reading
- de Bono, E. (1985) Six Thinking Hats. Boston, MA: Little, Brown; revised edition London: Penguin, 2000.
- de Bono, E. (1994) Parallel Thinking: From Socratic to de Bono Thinking. London: Viking.
- Moseley, D. et al. (2005) Frameworks for Thinking: A Handbook for Teaching and Learning. Cambridge: Cambridge University Press. ↗
- Nemeth, C. J., Personnaz, B., Personnaz, M. and Goncalo, J. A. (2004) 'The liberating role of conflict in group creativity: a study in two countries', European Journal of Social Psychology, 34(4), 365-374. ↗