To the Bedrock
The Garbage Can Model

Taxonomy

The Garbage Can Model uses three structural dimensions to describe how problems, participants, and choice opportunities interact. Their combination shapes the decisions that follow.

The Three Dimensions

Problem Pressure (Difficulty + Arrival Rate)

Pressure compares demand with the organisation's processing capacity. It combines problem difficulty, the effort per problem, and problem arrival rate, the new problems per organisational iteration. High pressure means demand exceeds what the system can absorb.

Light: capacity typically exceeds demand. Most problems find closure. Moderate: capacity and demand are often in tension. Some problems close, others circulate. Heavy: demand overwhelms capacity. Choice opportunities often close without resolving underlying problems.

Decision Structure

Who gets to participate in which choice opportunities. This determines where attention and effort actually go.

Open participation (non-segmented): all decision makers can attend all choice opportunities. Energy spreads everywhere. Hierarchical: senior decision makers access more choice opportunities. Energy concentrates at the top. Specialized: each decision maker attends only their designated choice opportunity. Energy is siloed.

Access Structure

Which problems can reach which choice opportunities. This determines whether problems even reach places where they could be resolved.

Open (non-segmented): any problem can surface in any choice opportunity. Problems float freely. Hierarchical: important problems access more choice opportunities. Lower-priority problems are restricted. Specialized: each problem is assigned to exactly one choice opportunity. No migration possible.

The Classification Grid

Decision structure plus access structure gives the organisation type. Problem pressure changes how severe the pattern feels, but it does not change the type.

The five labels in this site are working diagnostic labels for Explorer and Assess. They help interpretation in this module; they do not replace the original model terms.

Open access Hierarchical access Specialized access
Open participation decision Complexity-Informed Inverse Mix Inverse Mix
Hierarchical decision The Mix Coherent Traditional The Mix
Specialized decision Inverse Mix The Mix Siloed

Some decision/access combinations intentionally map to the same cluster in Explorer and Assess.

The Five Types

The Coherent Traditional Organisation

Hierarchical decision · Hierarchical access

Problems usually reach the right forums. Decisions are made by the people expected to make them. Governance and reporting lines are mostly aligned with the work, so the system behaves close to its formal design. In this case, the Garbage Can Model has less explanatory power.

The Complexity-Informed Organisation

Open participation decision · Open access

Problems can surface in many places, and participation follows expertise more than rank. This openness supports a different operating logic, with a risk to traceability. It can be hard to establish who decided what and whether the original problem was resolved or moved elsewhere.

The Mix

Hierarchical decision · Open or Specialized access

Emergent work is governed through hierarchical decision rights. Problems appear where the work happens, while authority sits elsewhere. Teams spend effort translating and escalating issues across this persistent structural gap.

The Inverse Mix

Open participation or Specialized decision · Hierarchical or Specialized access

Decision forums can respond once a problem reaches them, but access is filtered. Problems at the edges arrive slowly or never reach a forum, leaving decision makers ready to act on an incomplete picture.

The Siloed Organisation

Specialized decision · Specialized access

Fixed channels, owners, and forums leave cross-cutting problems between formal boundaries. An issue with no recognised owner can disappear from view or be handled informally outside governance.

Explore Further

See the model in action or assess your own organisation:

Explore Run the model with any parameter combination Assess Answer twelve questions and see your organisation modelled What's a Garbage Can? Follow problems, solutions, and participants into one choice opportunity (CO)