To the Bedrock
The Garbage Can Model

Organised Anarchy

Cohen, March and Olsen used organised anarchy for organisations with three recurring conditions: fuzzy preferences (goals shift or conflict), unclear technology (people do not fully understand how outcomes are produced), and fluid participation (who joins which decision varies). In that setting, decisions happen in mixed and improvised forums: garbage cans, or in the formal term, choice opportunities.

Universities were the original case study. But the description applies to any organisation where the work is emergent, the environment is complex, and management instruments were designed for a simpler system.

The Four Streams

The Garbage Can Model describes organisations as the intersection of four independent streams: problems that need attention, solutions that exist (or are introduced) whether or not a matching problem has been identified, participants whose attention drifts between choice opportunities, and choice opportunities where decisions could be made.

In a rational model, a problem surfaces, participants gather, solutions are evaluated, and a decision is made. In the garbage can model, these streams collide inside choice opportunities with no guarantee that the problem in the room matches the solution being offered, or that the participants present are the ones who understand either problem or solution. The streams meet inside the garbage can.

Three Ways a Decision Gets Made

The model identifies three styles of decision-making, only one of which involves actually solving the problem at hand.

Deliberation occurs when a problem attaches to a choice opportunity, sufficient energy accumulates, and the problem is genuinely resolved. This is what organisations believe happens most of the time. The garbage can model suggests it is the exception.

Oversight is when a decision closes cleanly but no real problem was attached. The meeting happened. The decision was recorded. The underlying issue lived elsewhere, so the organisation produced output without resolution.

Flight occurs when the problem leaves before the choice opportunity resolves. The issue gets raised, discussed, and then dropped as attention moves elsewhere. Nothing closes; the problem migrates.

Why This Matters

Most organisations operate as if decisions are made rationally: a problem is identified and defined, options are weighed, and a choice is made. Operating models, governance structures, reporting lines, and capital allocation processes are often built on this rationality assumption. The Garbage Can Model shows what happens when that assumption is wrong.

In high-pressure organisations, problems outnumber the system's capacity to resolve them. Choice opportunities close without addressing the issues that were raised. Problems migrate between meetings, reviews, and committees, never finding a stable place to be resolved. The organisation keeps producing decisions, while many problems remain unresolved.

In practice this can look mundane: a steering meeting closes, status turns green, and the same issue appears two weeks later in another forum under a different label.

The gap between the decisions being made and the problems being experienced is not a failure of allocation, communication or competence, but a structural property of the system.

Explore the Model

This module offers four ways to engage with the Garbage Can Model:

Taxonomy The five organisation types and how they are classified Explore Run the model with any parameter combination Assess Answer twelve questions and see your organisation modelled What's a Garbage Can? See the three streams collide in one choice opportunity

References

Cohen, M. D., March, J. G., & Olsen, J. P. (1972). A Garbage Can Model of Organizational Choice. Administrative Science Quarterly, 17(1), 1–25.