Organizing Squads into Tribes for Alignment

Group related squads into tribes with boundaries drawn from real dependencies, a size limit people can manage, and a tribe lead who keeps squads aligned.

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At a Glance

Overview

A tribe is a group of squads working in related areas of the product. In the Spotify model it is the layer that keeps autonomous squads aware of each other, reduces duplicated work, and gives them a shared place to learn. This skill covers drawing tribe boundaries, sizing tribes, choosing a tribe lead and setting up the few rituals a tribe needs.

The 2012 paper by Kniberg and Ivarsson describes a tribe as a collection of squads in related areas, such as the music player or backend infrastructure, and calls it the "incubator" for the squad mini-startups. Each tribe has a tribe lead responsible for providing the best possible habitat for its squads. At the time, the squads in a tribe sat in the same office, close to each other, and held regular gatherings to show what they were working on.

Size is the tribe's defining constraint. The paper cites the Dunbar number, the idea that most people cannot maintain social relationships with more than about a hundred others, and says tribes were designed to be smaller than 100 people or so (Kniberg and Ivarsson). Beyond that size, the paper says, groups start to grow restrictive rules, bureaucracy, politics and extra layers of management.

Later descriptions add leadership detail. Atlassian's summary describes a trio for each tribe, made up of the tribe lead, a product lead and a design lead, and alliances of tribe trios when several tribes must work on one goal (Atlassian). You do not need all of this at the start. The output of this skill is a tribe map: which squads belong to which tribe and why, the tribe's mission, its lead, its rituals and the interfaces it has with other tribes.

How It Works

A tribe boundary is a statement about where coordination should be cheap. Squads inside a tribe can talk informally, share a gathering and resolve most dependencies between themselves. Squads in different tribes coordinate through more deliberate channels. So the first principle is simple: put squads that depend on each other often in the same tribe.

That requires data on dependencies. The 2012 paper describes asking every squad which other squads it depends on and whether each dependency blocks it or only slows it down, then discussing how to remove the problem ones, especially blocking and cross-tribe dependencies. The same survey is the input for drawing tribes. Clusters of squads that depend heavily on each other are candidate tribes; squads with few dependencies can go where their product area fits best.

The size limit then tests the clusters. A cluster that would pass the Dunbar-inspired cap needs splitting along the weakest dependency line. Published ranges differ: Atlassian's summary gives tribes of typically 40-150 people (Atlassian), while the paper's own wording is smaller than 100 people or so. Pick a cap and apply it consistently.

The tribe lead builds the habitat and leaves the squads' projects to the squads. Their work is keeping the tribe's squads aligned to a shared direction, clearing obstacles that no squad can clear alone, and representing the tribe to the rest of the company. ING's version of the model gave tribes explicit alignment mechanisms, including portfolio wall planning, daily stand-ups to keep product owners aligned, and a quarterly business review in which each tribe records what it achieved, what it learned and which other tribes or squads it needs next quarter (McKinsey Quarterly).

Rituals should be few and useful. The 2012 paper describes informal tribe gatherings with live demos, new tools and hack-day projects, and on-demand coordination, such as a daily sync between squads during a large cross-squad project, rather than a standing scrum of scrums. Add ceremony only when a real coordination problem shows up.

Step-by-Step Guide

Step 1: Survey squad dependencies

Ask every squad which other squads it depends on, and whether each dependency blocks it or only slows it down. Record the answers in a simple table or graph. Include dependencies on platform and operations groups, since the 2012 paper noticed more and more squads being slowed down by operations. Repeat the survey later so you can see whether the structure is helping. This data is the foundation for every other step.

Step 2: Find natural clusters

Look for groups of squads with many mutual dependencies or a shared product area and customers. Draw candidate tribes around those groups. Check that each candidate has a coherent purpose you can state in a sentence, such as "everything a listener does on a mobile device". Avoid tribes drawn around technology layers, because nearly every user-facing change would then cross tribe lines.

Step 3: Apply the size limit

Count the people in each candidate tribe, including product owners, designers, coaches and chapter leads. If a tribe is over your cap, split it along the line with the fewest dependencies. If a tribe is very small, consider merging it with its closest neighbor so the tribe lead role and the rituals are worth their cost. Record the reasoning for each split and merge.

Step 4: Write the tribe mission

Give each tribe a mission that sits between company strategy and its squads' missions. Check that every squad mission in the tribe fits inside it and that no two tribes claim the same outcome. Keep it stable enough to last several planning cycles. Share it with the squads before finalizing, because they will spot overlaps leadership misses.

Step 5: Appoint the tribe lead and leadership group

Choose a tribe lead whose strength is coordination and removing obstacles rather than directing work. Decide whether the tribe lead works alongside product and design leads as a trio, as Atlassian's summary describes. Write down what the tribe lead decides, such as budget and staffing across squads, and what they leave to squads. Make clear that squads keep ownership of how they work.

Step 6: Set up a few tribe rituals

Start with a regular tribe gathering where squads demo what they shipped and share what others can reuse. Add a regular planning or review point where the tribe checks its squads against its mission and priorities. Use on-demand syncs for projects that need several squads rather than a permanent coordination meeting. Review the rituals after a quarter and drop any nobody would miss.

Step 7: Define cross-tribe interfaces

List the dependencies that still cross tribe lines after the boundaries are drawn. For each, name the owner on each side and how requests are made, whether by API contract, shared roadmap or a named contact. Where several tribes must work together on one goal, form a temporary alliance of their leadership rather than redrawing tribes. Revisit cross-tribe dependencies in the next dependency survey.

Step 8: Announce, then review

Explain the tribe map to everyone affected, including the reasoning for each boundary, before it takes effect. Invite challenges for a fixed period and adjust where squads show a better grouping. After launch, repeat the dependency survey each quarter. If squads in the same tribe rarely coordinate, or squads in different tribes block each other constantly, redraw the boundaries.

Best Practices

• Draw boundaries from dependency data rather than from the existing org chart. The old departments are often exactly the silos the tribes are meant to dissolve.
• Count everyone when checking size. Product owners, designers and coaches all add to the number of relationships people must keep up, which is the reason the size cap exists.
• Keep the tribe lead out of squad task assignment. A tribe lead who assigns work turns squads back into delivery teams and removes the reason for having them.
• Keep coordination on demand where you can. The 2012 paper notes that Spotify did not usually run a scrum of scrums because most squads were fairly independent, and set up a daily sync only when a large project needed several squads.
• Make tribe results visible across the company. ING's quarterly business review documents are open to all tribes, which lets tribes see each other's plans and ask for help early (McKinsey Quarterly).
• Revisit tribes when the product strategy changes. A boundary that fitted last year's priorities can put today's most important work across two tribes.

Common Mistakes

• Tribes that mirror old departments: Renaming departments as tribes keeps the old hand-offs. Start from the dependency survey and let the grouping follow the work.
• Letting tribes grow without limit: A tribe that keeps absorbing squads becomes a department with a tribe lead on top. Set a cap and split before it is reached.
• A tribe lead who runs the squads: When the tribe lead sets squad priorities and tasks, squads lose autonomy and the product owners lose their role. Keep the tribe lead focused on direction, obstacles and habitat.
• Heavy standing coordination: Weekly meetings for every squad lead add overhead that grows with each squad. Use gatherings for shared context and targeted syncs for real dependencies.
• Never redrawing boundaries: Products and priorities change. A tribe structure that is never reviewed slowly drifts out of line with the work.

References

• Examples: Worked examples and scenarios
• FAQ: Frequently asked questions
• Parent Method: The Spotify Model

Related Skills

• Forming Autonomous Squads with Clear Missions
• Scaling Agile with Spotify Squads and Tribes
• Balancing Squad Autonomy with Organizational Alignment
• Running Chapters for Craft Excellence
• Building Guilds for Cross-Tribe Knowledge Sharing
• Adapting the Spotify Model to Your Organization
• Evaluating Spotify Model Tradeoffs and Failure Modes

Sources

• Henrik Kniberg and Anders Ivarsson: Scaling Agile @ Spotify (2012)
• Atlassian: Discover the Spotify model
• McKinsey Quarterly: ING's agile transformation

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