The city is a town at scale.

The city is a town at a different scale.

The Scrum of Scrums is a common tool to scale Agile. In many cases the technique works admirably, however as Scrum-based Agile is applied to larger and larger projects, the Scrum of Scrums technique becomes stressed. The most significant issues include:

  1. As the number of Scrum teams involved on a project increases, the number of attendees increase. As the number of attendees that must talk in a meeting increases, the length of the meeting increases. The length of meeting is perfectly correlated to the number of emails sent by participant during the meeting. In other words, it is difficult to hold the attention of participants in larger, long meeting meetings. As projects grow, curtail the active participants to the team Scrum master /representative. In organizations where product owners wish to hold a Scrum of Scrum type meeting make sure those sessions are separated. I have also seen organizations experiment with hierarchies of Scrum of Scrums meetings.
  2. Project Coordination. Both Scrum of Scrum meetings and their cousins, daily stand-up meetings, are coordination and planning meetings. As the project size grows, coordination and planning meetings require greater context (status) to be effective, which can shift the focus towards informational or status meetings thereby reducing the effectiveness of the technique. Large projects need to have a mechanism for sharing context/status outside of planning and coordination meetings. One interesting solution I have observed (for a large program) was a daily program e-newsletter akin to the newsletter large conferences publish daily. I have also seen status wikis used to great effect. Status and news is easily consumed asynchronously therefore meeting time can be avoided.
  3. The Scrum of Scrums meeting infers a hierarchy in Scrum teams that does not exist. Scrum masters become the conduit of information between teams. Team communicate with their Scrum masters, Scrum masters communicate with other Scrum Masters then to the team they are part of and then the cycle reverses. A few years ago I read an article by Mike Cohn that suggested rotating participation. While rotation might impact the consistency, it would send a message that participation is a role rather than a status level.

Scaling Agile requires thought and planning. A Scrum of Scrums that includes product owners and other participants that worked for a handful of teams might need to be tailored when the project grows to include two or three handfuls of teams. Very few human institutions are linearly scalable forever. When using Scrum of Scrums for larger programs scale the technique rather than just moving to a larger conference room.